From 4876af06ddb280b0a01903c1da17466b13124eb3 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Thu, 23 Jul 2020 16:52:33 +0100
Subject: Abort federation requests if the client disconnects early (#7930)

For inbound federation requests, if a given remote server makes too many
requests at once, we start stacking them up rather than processing them
immediatedly.

However, that means that there is a fair chance that the requesting server will
disconnect before we start processing the request. In that case, if it was a
read-only request (ie, a GET request), there is absolutely no point in
building a response (and some requests are quite expensive to handle).

Even in the case of a POST request, one of two things will happen:

 * Most likely, the requesting server will retry the request and we'll get the
   information anyway.

 * Even if it doesn't, the requesting server has to assume that we didn't get
   the memo, and act accordingly.

In short, we're better off aborting the request at this point rather than
ploughing on with what might be a quite expensive request.
---
 synapse/federation/transport/server.py | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'synapse/federation')

diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 24f7d4b3bc..5e111aa902 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -338,6 +338,12 @@ class BaseFederationServlet(object):
                 if origin:
                     with ratelimiter.ratelimit(origin) as d:
                         await d
+                        if request._disconnected:
+                            logger.warning(
+                                "client disconnected before we started processing "
+                                "request"
+                            )
+                            return -1, None
                         response = await func(
                             origin, content, request.args, *args, **kwargs
                         )
-- 
cgit 1.5.1


From 7078866969758e52eec33ebdb8288e203d8bd2b7 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Thu, 23 Jul 2020 18:38:19 +0100
Subject: Put a cache on `/state_ids` (#7931)

If we send out an event which refers to `prev_events` which other servers in
the federation are missing, then (after a round or two of backfill attempts),
they will end up asking us for `/state_ids` at a particular point in the DAG.

As per https://github.com/matrix-org/synapse/issues/7893, this is quite
expensive, and we tend to see lots of very similar requests around the same
time.

We can therefore handle this much more efficiently by using a cache, which (a)
ensures that if we see the same request from multiple servers (or even the same
server, multiple times), then they share the result, and (b) any other servers
that miss the initial excitement can also benefit from the work.

[It's interesting to note that `/state` has a cache for exactly this
reason. `/state` is now essentially unused and replaced with `/state_ids`, but
evidently when we replaced it we forgot to add a cache to the new endpoint.]
---
 changelog.d/7931.feature                |  1 +
 synapse/federation/federation_server.py | 13 +++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/7931.feature

(limited to 'synapse/federation')

diff --git a/changelog.d/7931.feature b/changelog.d/7931.feature
new file mode 100644
index 0000000000..30eb33048b
--- /dev/null
+++ b/changelog.d/7931.feature
@@ -0,0 +1 @@
+Cache responses to `/_matrix/federation/v1/state_ids` to reduce duplicated work.
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index 23625ba995..11c5d63298 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -109,6 +109,9 @@ class FederationServer(FederationBase):
         # We cache responses to state queries, as they take a while and often
         # come in waves.
         self._state_resp_cache = ResponseCache(hs, "state_resp", timeout_ms=30000)
+        self._state_ids_resp_cache = ResponseCache(
+            hs, "state_ids_resp", timeout_ms=30000
+        )
 
     async def on_backfill_request(
         self, origin: str, room_id: str, versions: List[str], limit: int
@@ -376,10 +379,16 @@ class FederationServer(FederationBase):
         if not in_room:
             raise AuthError(403, "Host not in room.")
 
+        resp = await self._state_ids_resp_cache.wrap(
+            (room_id, event_id), self._on_state_ids_request_compute, room_id, event_id,
+        )
+
+        return 200, resp
+
+    async def _on_state_ids_request_compute(self, room_id, event_id):
         state_ids = await self.handler.get_state_ids_for_pdu(room_id, event_id)
         auth_chain_ids = await self.store.get_auth_chain_ids(state_ids)
-
-        return 200, {"pdu_ids": state_ids, "auth_chain_ids": auth_chain_ids}
+        return {"pdu_ids": state_ids, "auth_chain_ids": auth_chain_ids}
 
     async def _on_context_state_request_compute(
         self, room_id: str, event_id: str
-- 
cgit 1.5.1


From fefe9943ef008b00bc85f80a486323279e63d117 Mon Sep 17 00:00:00 2001
From: Patrick Cloke <clokep@users.noreply.github.com>
Date: Thu, 23 Jul 2020 16:47:36 -0400
Subject: Convert presence handler helpers to async/await. (#7939)

---
 changelog.d/7939.misc                 |  1 +
 synapse/federation/sender/__init__.py |  4 +++-
 synapse/handlers/presence.py          | 43 ++++++++++++++++-------------------
 3 files changed, 24 insertions(+), 24 deletions(-)
 create mode 100644 changelog.d/7939.misc

(limited to 'synapse/federation')

diff --git a/changelog.d/7939.misc b/changelog.d/7939.misc
new file mode 100644
index 0000000000..798833b3af
--- /dev/null
+++ b/changelog.d/7939.misc
@@ -0,0 +1 @@
+Convert presence handler helpers to async/await.
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index b328a4df09..99ce73e081 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -453,7 +453,9 @@ class FederationSender(object):
         """Given a list of states populate self.pending_presence_by_dest and
         poke to send a new transaction to each destination
         """
-        hosts_and_states = yield get_interested_remotes(self.store, states, self.state)
+        hosts_and_states = yield defer.ensureDeferred(
+            get_interested_remotes(self.store, states, self.state)
+        )
 
         for destinations, states in hosts_and_states:
             for destination in destinations:
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index d2f25ae12a..8e99c83d9d 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -30,8 +30,6 @@ from typing import Dict, Iterable, List, Set, Tuple
 from prometheus_client import Counter
 from typing_extensions import ContextManager
 
-from twisted.internet import defer
-
 import synapse.metrics
 from synapse.api.constants import EventTypes, Membership, PresenceState
 from synapse.api.errors import SynapseError
@@ -39,6 +37,8 @@ from synapse.logging.context import run_in_background
 from synapse.logging.utils import log_function
 from synapse.metrics import LaterGauge
 from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.state import StateHandler
+from synapse.storage.data_stores.main import DataStore
 from synapse.storage.presence import UserPresenceState
 from synapse.types import JsonDict, UserID, get_domain_from_id
 from synapse.util.async_helpers import Linearizer
@@ -895,16 +895,9 @@ class PresenceHandler(BasePresenceHandler):
 
             await self._on_user_joined_room(room_id, state_key)
 
-    async def _on_user_joined_room(self, room_id, user_id):
+    async def _on_user_joined_room(self, room_id: str, user_id: str) -> None:
         """Called when we detect a user joining the room via the current state
         delta stream.
-
-        Args:
-            room_id (str)
-            user_id (str)
-
-        Returns:
-            Deferred
         """
 
         if self.is_mine_id(user_id):
@@ -1296,22 +1289,24 @@ def handle_update(prev_state, new_state, is_mine, wheel_timer, now):
     return new_state, persist_and_notify, federation_ping
 
 
-@defer.inlineCallbacks
-def get_interested_parties(store, states):
+async def get_interested_parties(
+    store: DataStore, states: List[UserPresenceState]
+) -> Tuple[Dict[str, List[UserPresenceState]], Dict[str, List[UserPresenceState]]]:
     """Given a list of states return which entities (rooms, users)
     are interested in the given states.
 
     Args:
-        states (list(UserPresenceState))
+        store
+        states
 
     Returns:
-        2-tuple: `(room_ids_to_states, users_to_states)`,
+        A 2-tuple of `(room_ids_to_states, users_to_states)`,
         with each item being a dict of `entity_name` -> `[UserPresenceState]`
     """
     room_ids_to_states = {}  # type: Dict[str, List[UserPresenceState]]
     users_to_states = {}  # type: Dict[str, List[UserPresenceState]]
     for state in states:
-        room_ids = yield store.get_rooms_for_user(state.user_id)
+        room_ids = await store.get_rooms_for_user(state.user_id)
         for room_id in room_ids:
             room_ids_to_states.setdefault(room_id, []).append(state)
 
@@ -1321,20 +1316,22 @@ def get_interested_parties(store, states):
     return room_ids_to_states, users_to_states
 
 
-@defer.inlineCallbacks
-def get_interested_remotes(store, states, state_handler):
+async def get_interested_remotes(
+    store: DataStore, states: List[UserPresenceState], state_handler: StateHandler
+) -> List[Tuple[List[str], List[UserPresenceState]]]:
     """Given a list of presence states figure out which remote servers
     should be sent which.
 
     All the presence states should be for local users only.
 
     Args:
-        store (DataStore)
-        states (list(UserPresenceState))
+        store
+        states
+        state_handler
 
     Returns:
-        Deferred list of ([destinations], [UserPresenceState]), where for
-        each row the list of UserPresenceState should be sent to each
+        A list of 2-tuples of destinations and states, where for
+        each tuple the list of UserPresenceState should be sent to each
         destination
     """
     hosts_and_states = []
@@ -1342,10 +1339,10 @@ def get_interested_remotes(store, states, state_handler):
     # First we look up the rooms each user is in (as well as any explicit
     # subscriptions), then for each distinct room we look up the remote
     # hosts in those rooms.
-    room_ids_to_states, users_to_states = yield get_interested_parties(store, states)
+    room_ids_to_states, users_to_states = await get_interested_parties(store, states)
 
     for room_id, states in room_ids_to_states.items():
-        hosts = yield state_handler.get_current_hosts_in_room(room_id)
+        hosts = await state_handler.get_current_hosts_in_room(room_id)
         hosts_and_states.append((hosts, states))
 
     for user_id, states in users_to_states.items():
-- 
cgit 1.5.1


From b975fa2e9952f1f8ac2cddb15c287768bf9b0b4e Mon Sep 17 00:00:00 2001
From: Patrick Cloke <clokep@users.noreply.github.com>
Date: Fri, 24 Jul 2020 10:59:51 -0400
Subject: Convert state resolution to async/await (#7942)

---
 changelog.d/7942.misc                              |   1 +
 synapse/api/auth.py                                |  12 ++-
 synapse/events/builder.py                          |   4 +-
 synapse/federation/sender/__init__.py              |   4 +-
 synapse/handlers/presence.py                       |   4 +-
 synapse/push/bulk_push_rule_evaluator.py           |   4 +-
 synapse/state/__init__.py                          |  95 ++++++++----------
 synapse/state/v1.py                                |  15 ++-
 synapse/state/v2.py                                | 107 ++++++++++-----------
 synapse/storage/data_stores/main/push_rule.py      |   2 +-
 synapse/storage/data_stores/main/roommember.py     |   2 +-
 synapse/storage/data_stores/main/user_directory.py |   4 +-
 synapse/storage/persist_events.py                  |   5 +-
 tests/federation/test_federation_sender.py         |  19 ++--
 tests/state/test_v2.py                             |  17 ++--
 tests/storage/test_room.py                         |   8 +-
 tests/test_state.py                                |  72 ++++++++------
 tests/test_utils/__init__.py                       |   7 +-
 18 files changed, 198 insertions(+), 184 deletions(-)
 create mode 100644 changelog.d/7942.misc

(limited to 'synapse/federation')

diff --git a/changelog.d/7942.misc b/changelog.d/7942.misc
new file mode 100644
index 0000000000..b504cf4e6f
--- /dev/null
+++ b/changelog.d/7942.misc
@@ -0,0 +1 @@
+Convert state resolution to async/await.
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index 40dc62ef6c..b53e8451e5 100644
--- a/synapse/api/auth.py
+++ b/synapse/api/auth.py
@@ -127,8 +127,10 @@ class Auth(object):
         if current_state:
             member = current_state.get((EventTypes.Member, user_id), None)
         else:
-            member = yield self.state.get_current_state(
-                room_id=room_id, event_type=EventTypes.Member, state_key=user_id
+            member = yield defer.ensureDeferred(
+                self.state.get_current_state(
+                    room_id=room_id, event_type=EventTypes.Member, state_key=user_id
+                )
             )
         membership = member.membership if member else None
 
@@ -665,8 +667,10 @@ class Auth(object):
             )
             return member_event.membership, member_event.event_id
         except AuthError:
-            visibility = yield self.state.get_current_state(
-                room_id, EventTypes.RoomHistoryVisibility, ""
+            visibility = yield defer.ensureDeferred(
+                self.state.get_current_state(
+                    room_id, EventTypes.RoomHistoryVisibility, ""
+                )
             )
             if (
                 visibility
diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index 92aadfe7ef..0bb216419a 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -106,8 +106,8 @@ class EventBuilder(object):
             Deferred[FrozenEvent]
         """
 
-        state_ids = yield self._state.get_current_state_ids(
-            self.room_id, prev_event_ids
+        state_ids = yield defer.ensureDeferred(
+            self._state.get_current_state_ids(self.room_id, prev_event_ids)
         )
         auth_ids = yield self._auth.compute_auth_events(self, state_ids)
 
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index 99ce73e081..ba4ddd2370 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -330,7 +330,9 @@ class FederationSender(object):
         room_id = receipt.room_id
 
         # Work out which remote servers should be poked and poke them.
-        domains = yield self.state.get_current_hosts_in_room(room_id)
+        domains = yield defer.ensureDeferred(
+            self.state.get_current_hosts_in_room(room_id)
+        )
         domains = [
             d
             for d in domains
diff --git a/synapse/handlers/presence.py b/synapse/handlers/presence.py
index 8e99c83d9d..b3a3bb8c3f 100644
--- a/synapse/handlers/presence.py
+++ b/synapse/handlers/presence.py
@@ -928,8 +928,8 @@ class PresenceHandler(BasePresenceHandler):
             # TODO: Check that this is actually a new server joining the
             # room.
 
-            user_ids = await self.state.get_current_users_in_room(room_id)
-            user_ids = list(filter(self.is_mine_id, user_ids))
+            users = await self.state.get_current_users_in_room(room_id)
+            user_ids = list(filter(self.is_mine_id, users))
 
             states_d = await self.current_state_for_users(user_ids)
 
diff --git a/synapse/push/bulk_push_rule_evaluator.py b/synapse/push/bulk_push_rule_evaluator.py
index 43ffe6faf0..472ddf9f7d 100644
--- a/synapse/push/bulk_push_rule_evaluator.py
+++ b/synapse/push/bulk_push_rule_evaluator.py
@@ -304,7 +304,9 @@ class RulesForRoom(object):
 
                 push_rules_delta_state_cache_metric.inc_hits()
             else:
-                current_state_ids = yield context.get_current_state_ids()
+                current_state_ids = yield defer.ensureDeferred(
+                    context.get_current_state_ids()
+                )
                 push_rules_delta_state_cache_metric.inc_misses()
 
             push_rules_state_size_counter.inc(len(current_state_ids))
diff --git a/synapse/state/__init__.py b/synapse/state/__init__.py
index 495d9f04c8..25ccef5aa5 100644
--- a/synapse/state/__init__.py
+++ b/synapse/state/__init__.py
@@ -16,14 +16,12 @@
 
 import logging
 from collections import namedtuple
-from typing import Dict, Iterable, List, Optional, Set
+from typing import Awaitable, Dict, Iterable, List, Optional, Set
 
 import attr
 from frozendict import frozendict
 from prometheus_client import Histogram
 
-from twisted.internet import defer
-
 from synapse.api.constants import EventTypes
 from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, StateResolutionVersions
 from synapse.events import EventBase
@@ -31,6 +29,7 @@ from synapse.events.snapshot import EventContext
 from synapse.logging.utils import log_function
 from synapse.state import v1, v2
 from synapse.storage.data_stores.main.events_worker import EventRedactBehaviour
+from synapse.storage.roommember import ProfileInfo
 from synapse.types import StateMap
 from synapse.util import Clock
 from synapse.util.async_helpers import Linearizer
@@ -108,8 +107,7 @@ class StateHandler(object):
         self.hs = hs
         self._state_resolution_handler = hs.get_state_resolution_handler()
 
-    @defer.inlineCallbacks
-    def get_current_state(
+    async def get_current_state(
         self, room_id, event_type=None, state_key="", latest_event_ids=None
     ):
         """ Retrieves the current state for the room. This is done by
@@ -126,20 +124,20 @@ class StateHandler(object):
             map from (type, state_key) to event
         """
         if not latest_event_ids:
-            latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
+            latest_event_ids = await self.store.get_latest_event_ids_in_room(room_id)
 
         logger.debug("calling resolve_state_groups from get_current_state")
-        ret = yield self.resolve_state_groups_for_events(room_id, latest_event_ids)
+        ret = await self.resolve_state_groups_for_events(room_id, latest_event_ids)
         state = ret.state
 
         if event_type:
             event_id = state.get((event_type, state_key))
             event = None
             if event_id:
-                event = yield self.store.get_event(event_id, allow_none=True)
+                event = await self.store.get_event(event_id, allow_none=True)
             return event
 
-        state_map = yield self.store.get_events(
+        state_map = await self.store.get_events(
             list(state.values()), get_prev_content=False
         )
         state = {
@@ -148,8 +146,7 @@ class StateHandler(object):
 
         return state
 
-    @defer.inlineCallbacks
-    def get_current_state_ids(self, room_id, latest_event_ids=None):
+    async def get_current_state_ids(self, room_id, latest_event_ids=None):
         """Get the current state, or the state at a set of events, for a room
 
         Args:
@@ -164,41 +161,38 @@ class StateHandler(object):
                 (event_type, state_key) -> event_id
         """
         if not latest_event_ids:
-            latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
+            latest_event_ids = await self.store.get_latest_event_ids_in_room(room_id)
 
         logger.debug("calling resolve_state_groups from get_current_state_ids")
-        ret = yield self.resolve_state_groups_for_events(room_id, latest_event_ids)
+        ret = await self.resolve_state_groups_for_events(room_id, latest_event_ids)
         state = ret.state
 
         return state
 
-    @defer.inlineCallbacks
-    def get_current_users_in_room(self, room_id, latest_event_ids=None):
+    async def get_current_users_in_room(
+        self, room_id: str, latest_event_ids: Optional[List[str]] = None
+    ) -> Dict[str, ProfileInfo]:
         """
         Get the users who are currently in a room.
 
         Args:
-            room_id (str): The ID of the room.
-            latest_event_ids (List[str]|None): Precomputed list of latest
-                event IDs. Will be computed if None.
+            room_id: The ID of the room.
+            latest_event_ids: Precomputed list of latest event IDs. Will be computed if None.
         Returns:
-            Deferred[Dict[str,ProfileInfo]]: Dictionary of user IDs to their
-                profileinfo.
+            Dictionary of user IDs to their profileinfo.
         """
         if not latest_event_ids:
-            latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
+            latest_event_ids = await self.store.get_latest_event_ids_in_room(room_id)
         logger.debug("calling resolve_state_groups from get_current_users_in_room")
-        entry = yield self.resolve_state_groups_for_events(room_id, latest_event_ids)
-        joined_users = yield self.store.get_joined_users_from_state(room_id, entry)
+        entry = await self.resolve_state_groups_for_events(room_id, latest_event_ids)
+        joined_users = await self.store.get_joined_users_from_state(room_id, entry)
         return joined_users
 
-    @defer.inlineCallbacks
-    def get_current_hosts_in_room(self, room_id):
-        event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
-        return (yield self.get_hosts_in_room_at_events(room_id, event_ids))
+    async def get_current_hosts_in_room(self, room_id):
+        event_ids = await self.store.get_latest_event_ids_in_room(room_id)
+        return await self.get_hosts_in_room_at_events(room_id, event_ids)
 
-    @defer.inlineCallbacks
-    def get_hosts_in_room_at_events(self, room_id, event_ids):
+    async def get_hosts_in_room_at_events(self, room_id, event_ids):
         """Get the hosts that were in a room at the given event ids
 
         Args:
@@ -208,12 +202,11 @@ class StateHandler(object):
         Returns:
             Deferred[list[str]]: the hosts in the room at the given events
         """
-        entry = yield self.resolve_state_groups_for_events(room_id, event_ids)
-        joined_hosts = yield self.store.get_joined_hosts(room_id, entry)
+        entry = await self.resolve_state_groups_for_events(room_id, event_ids)
+        joined_hosts = await self.store.get_joined_hosts(room_id, entry)
         return joined_hosts
 
-    @defer.inlineCallbacks
-    def compute_event_context(
+    async def compute_event_context(
         self, event: EventBase, old_state: Optional[Iterable[EventBase]] = None
     ):
         """Build an EventContext structure for the event.
@@ -278,7 +271,7 @@ class StateHandler(object):
             # otherwise, we'll need to resolve the state across the prev_events.
             logger.debug("calling resolve_state_groups from compute_event_context")
 
-            entry = yield self.resolve_state_groups_for_events(
+            entry = await self.resolve_state_groups_for_events(
                 event.room_id, event.prev_event_ids()
             )
 
@@ -295,7 +288,7 @@ class StateHandler(object):
         #
 
         if not state_group_before_event:
-            state_group_before_event = yield self.state_store.store_state_group(
+            state_group_before_event = await self.state_store.store_state_group(
                 event.event_id,
                 event.room_id,
                 prev_group=state_group_before_event_prev_group,
@@ -335,7 +328,7 @@ class StateHandler(object):
         state_ids_after_event[key] = event.event_id
         delta_ids = {key: event.event_id}
 
-        state_group_after_event = yield self.state_store.store_state_group(
+        state_group_after_event = await self.state_store.store_state_group(
             event.event_id,
             event.room_id,
             prev_group=state_group_before_event,
@@ -353,8 +346,7 @@ class StateHandler(object):
         )
 
     @measure_func()
-    @defer.inlineCallbacks
-    def resolve_state_groups_for_events(self, room_id, event_ids):
+    async def resolve_state_groups_for_events(self, room_id, event_ids):
         """ Given a list of event_ids this method fetches the state at each
         event, resolves conflicts between them and returns them.
 
@@ -373,7 +365,7 @@ class StateHandler(object):
         # map from state group id to the state in that state group (where
         # 'state' is a map from state key to event id)
         # dict[int, dict[(str, str), str]]
-        state_groups_ids = yield self.state_store.get_state_groups_ids(
+        state_groups_ids = await self.state_store.get_state_groups_ids(
             room_id, event_ids
         )
 
@@ -382,7 +374,7 @@ class StateHandler(object):
         elif len(state_groups_ids) == 1:
             name, state_list = list(state_groups_ids.items()).pop()
 
-            prev_group, delta_ids = yield self.state_store.get_state_group_delta(name)
+            prev_group, delta_ids = await self.state_store.get_state_group_delta(name)
 
             return _StateCacheEntry(
                 state=state_list,
@@ -391,9 +383,9 @@ class StateHandler(object):
                 delta_ids=delta_ids,
             )
 
-        room_version = yield self.store.get_room_version_id(room_id)
+        room_version = await self.store.get_room_version_id(room_id)
 
-        result = yield self._state_resolution_handler.resolve_state_groups(
+        result = await self._state_resolution_handler.resolve_state_groups(
             room_id,
             room_version,
             state_groups_ids,
@@ -402,8 +394,7 @@ class StateHandler(object):
         )
         return result
 
-    @defer.inlineCallbacks
-    def resolve_events(self, room_version, state_sets, event):
+    async def resolve_events(self, room_version, state_sets, event):
         logger.info(
             "Resolving state for %s with %d groups", event.room_id, len(state_sets)
         )
@@ -414,7 +405,7 @@ class StateHandler(object):
         state_map = {ev.event_id: ev for st in state_sets for ev in st}
 
         with Measure(self.clock, "state._resolve_events"):
-            new_state = yield resolve_events_with_store(
+            new_state = await resolve_events_with_store(
                 self.clock,
                 event.room_id,
                 room_version,
@@ -451,9 +442,8 @@ class StateResolutionHandler(object):
             reset_expiry_on_get=True,
         )
 
-    @defer.inlineCallbacks
     @log_function
-    def resolve_state_groups(
+    async def resolve_state_groups(
         self, room_id, room_version, state_groups_ids, event_map, state_res_store
     ):
         """Resolves conflicts between a set of state groups
@@ -479,13 +469,13 @@ class StateResolutionHandler(object):
             state_res_store (StateResolutionStore)
 
         Returns:
-            Deferred[_StateCacheEntry]: resolved state
+            _StateCacheEntry: resolved state
         """
         logger.debug("resolve_state_groups state_groups %s", state_groups_ids.keys())
 
         group_names = frozenset(state_groups_ids.keys())
 
-        with (yield self.resolve_linearizer.queue(group_names)):
+        with (await self.resolve_linearizer.queue(group_names)):
             if self._state_cache is not None:
                 cache = self._state_cache.get(group_names, None)
                 if cache:
@@ -517,7 +507,7 @@ class StateResolutionHandler(object):
             if conflicted_state:
                 logger.info("Resolving conflicted state for %r", room_id)
                 with Measure(self.clock, "state._resolve_events"):
-                    new_state = yield resolve_events_with_store(
+                    new_state = await resolve_events_with_store(
                         self.clock,
                         room_id,
                         room_version,
@@ -598,7 +588,7 @@ def resolve_events_with_store(
     state_sets: List[StateMap[str]],
     event_map: Optional[Dict[str, EventBase]],
     state_res_store: "StateResolutionStore",
-):
+) -> Awaitable[StateMap[str]]:
     """
     Args:
         room_id: the room we are working in
@@ -619,8 +609,7 @@ def resolve_events_with_store(
         state_res_store: a place to fetch events from
 
     Returns:
-        Deferred[dict[(str, str), str]]:
-            a map from (type, state_key) to event_id.
+        a map from (type, state_key) to event_id.
     """
     v = KNOWN_ROOM_VERSIONS[room_version]
     if v.state_res == StateResolutionVersions.V1:
diff --git a/synapse/state/v1.py b/synapse/state/v1.py
index 7b531a8337..ab5e24841d 100644
--- a/synapse/state/v1.py
+++ b/synapse/state/v1.py
@@ -15,9 +15,7 @@
 
 import hashlib
 import logging
-from typing import Callable, Dict, List, Optional
-
-from twisted.internet import defer
+from typing import Awaitable, Callable, Dict, List, Optional
 
 from synapse import event_auth
 from synapse.api.constants import EventTypes
@@ -32,12 +30,11 @@ logger = logging.getLogger(__name__)
 POWER_KEY = (EventTypes.PowerLevels, "")
 
 
-@defer.inlineCallbacks
-def resolve_events_with_store(
+async def resolve_events_with_store(
     room_id: str,
     state_sets: List[StateMap[str]],
     event_map: Optional[Dict[str, EventBase]],
-    state_map_factory: Callable,
+    state_map_factory: Callable[[List[str]], Awaitable],
 ):
     """
     Args:
@@ -56,7 +53,7 @@ def resolve_events_with_store(
 
         state_map_factory: will be called
             with a list of event_ids that are needed, and should return with
-            a Deferred of dict of event_id to event.
+            an Awaitable that resolves to a dict of event_id to event.
 
     Returns:
         Deferred[dict[(str, str), str]]:
@@ -80,7 +77,7 @@ def resolve_events_with_store(
 
     # dict[str, FrozenEvent]: a map from state event id to event. Only includes
     # the state events which are in conflict (and those in event_map)
-    state_map = yield state_map_factory(needed_events)
+    state_map = await state_map_factory(needed_events)
     if event_map is not None:
         state_map.update(event_map)
 
@@ -110,7 +107,7 @@ def resolve_events_with_store(
         "Asking for %d/%d auth events", len(new_needed_events), new_needed_event_count
     )
 
-    state_map_new = yield state_map_factory(new_needed_events)
+    state_map_new = await state_map_factory(new_needed_events)
     for event in state_map_new.values():
         if event.room_id != room_id:
             raise Exception(
diff --git a/synapse/state/v2.py b/synapse/state/v2.py
index bf6caa0946..6634955cdc 100644
--- a/synapse/state/v2.py
+++ b/synapse/state/v2.py
@@ -18,8 +18,6 @@ import itertools
 import logging
 from typing import Dict, List, Optional
 
-from twisted.internet import defer
-
 import synapse.state
 from synapse import event_auth
 from synapse.api.constants import EventTypes
@@ -32,14 +30,13 @@ from synapse.util import Clock
 logger = logging.getLogger(__name__)
 
 
-# We want to yield to the reactor occasionally during state res when dealing
+# We want to await to the reactor occasionally during state res when dealing
 # with large data sets, so that we don't exhaust the reactor. This is done by
-# yielding to reactor during loops every N iterations.
-_YIELD_AFTER_ITERATIONS = 100
+# awaiting to reactor during loops every N iterations.
+_AWAIT_AFTER_ITERATIONS = 100
 
 
-@defer.inlineCallbacks
-def resolve_events_with_store(
+async def resolve_events_with_store(
     clock: Clock,
     room_id: str,
     room_version: str,
@@ -87,7 +84,7 @@ def resolve_events_with_store(
 
     # Also fetch all auth events that appear in only some of the state sets'
     # auth chains.
-    auth_diff = yield _get_auth_chain_difference(state_sets, event_map, state_res_store)
+    auth_diff = await _get_auth_chain_difference(state_sets, event_map, state_res_store)
 
     full_conflicted_set = set(
         itertools.chain(
@@ -95,7 +92,7 @@ def resolve_events_with_store(
         )
     )
 
-    events = yield state_res_store.get_events(
+    events = await state_res_store.get_events(
         [eid for eid in full_conflicted_set if eid not in event_map],
         allow_rejected=True,
     )
@@ -118,14 +115,14 @@ def resolve_events_with_store(
         eid for eid in full_conflicted_set if _is_power_event(event_map[eid])
     )
 
-    sorted_power_events = yield _reverse_topological_power_sort(
+    sorted_power_events = await _reverse_topological_power_sort(
         clock, room_id, power_events, event_map, state_res_store, full_conflicted_set
     )
 
     logger.debug("sorted %d power events", len(sorted_power_events))
 
     # Now sequentially auth each one
-    resolved_state = yield _iterative_auth_checks(
+    resolved_state = await _iterative_auth_checks(
         clock,
         room_id,
         room_version,
@@ -148,13 +145,13 @@ def resolve_events_with_store(
     logger.debug("sorting %d remaining events", len(leftover_events))
 
     pl = resolved_state.get((EventTypes.PowerLevels, ""), None)
-    leftover_events = yield _mainline_sort(
+    leftover_events = await _mainline_sort(
         clock, room_id, leftover_events, pl, event_map, state_res_store
     )
 
     logger.debug("resolving remaining events")
 
-    resolved_state = yield _iterative_auth_checks(
+    resolved_state = await _iterative_auth_checks(
         clock,
         room_id,
         room_version,
@@ -174,8 +171,7 @@ def resolve_events_with_store(
     return resolved_state
 
 
-@defer.inlineCallbacks
-def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
+async def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
     """Return the power level of the sender of the given event according to
     their auth events.
 
@@ -188,11 +184,11 @@ def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
     Returns:
         Deferred[int]
     """
-    event = yield _get_event(room_id, event_id, event_map, state_res_store)
+    event = await _get_event(room_id, event_id, event_map, state_res_store)
 
     pl = None
     for aid in event.auth_event_ids():
-        aev = yield _get_event(
+        aev = await _get_event(
             room_id, aid, event_map, state_res_store, allow_none=True
         )
         if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
@@ -202,7 +198,7 @@ def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
     if pl is None:
         # Couldn't find power level. Check if they're the creator of the room
         for aid in event.auth_event_ids():
-            aev = yield _get_event(
+            aev = await _get_event(
                 room_id, aid, event_map, state_res_store, allow_none=True
             )
             if aev and (aev.type, aev.state_key) == (EventTypes.Create, ""):
@@ -221,8 +217,7 @@ def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store):
         return int(level)
 
 
-@defer.inlineCallbacks
-def _get_auth_chain_difference(state_sets, event_map, state_res_store):
+async def _get_auth_chain_difference(state_sets, event_map, state_res_store):
     """Compare the auth chains of each state set and return the set of events
     that only appear in some but not all of the auth chains.
 
@@ -235,7 +230,7 @@ def _get_auth_chain_difference(state_sets, event_map, state_res_store):
         Deferred[set[str]]: Set of event IDs
     """
 
-    difference = yield state_res_store.get_auth_chain_difference(
+    difference = await state_res_store.get_auth_chain_difference(
         [set(state_set.values()) for state_set in state_sets]
     )
 
@@ -292,8 +287,7 @@ def _is_power_event(event):
     return False
 
 
-@defer.inlineCallbacks
-def _add_event_and_auth_chain_to_graph(
+async def _add_event_and_auth_chain_to_graph(
     graph, room_id, event_id, event_map, state_res_store, auth_diff
 ):
     """Helper function for _reverse_topological_power_sort that add the event
@@ -314,7 +308,7 @@ def _add_event_and_auth_chain_to_graph(
         eid = state.pop()
         graph.setdefault(eid, set())
 
-        event = yield _get_event(room_id, eid, event_map, state_res_store)
+        event = await _get_event(room_id, eid, event_map, state_res_store)
         for aid in event.auth_event_ids():
             if aid in auth_diff:
                 if aid not in graph:
@@ -323,8 +317,7 @@ def _add_event_and_auth_chain_to_graph(
                 graph.setdefault(eid, set()).add(aid)
 
 
-@defer.inlineCallbacks
-def _reverse_topological_power_sort(
+async def _reverse_topological_power_sort(
     clock, room_id, event_ids, event_map, state_res_store, auth_diff
 ):
     """Returns a list of the event_ids sorted by reverse topological ordering,
@@ -344,26 +337,26 @@ def _reverse_topological_power_sort(
 
     graph = {}
     for idx, event_id in enumerate(event_ids, start=1):
-        yield _add_event_and_auth_chain_to_graph(
+        await _add_event_and_auth_chain_to_graph(
             graph, room_id, event_id, event_map, state_res_store, auth_diff
         )
 
-        # We yield occasionally when we're working with large data sets to
+        # We await occasionally when we're working with large data sets to
         # ensure that we don't block the reactor loop for too long.
-        if idx % _YIELD_AFTER_ITERATIONS == 0:
-            yield clock.sleep(0)
+        if idx % _AWAIT_AFTER_ITERATIONS == 0:
+            await clock.sleep(0)
 
     event_to_pl = {}
     for idx, event_id in enumerate(graph, start=1):
-        pl = yield _get_power_level_for_sender(
+        pl = await _get_power_level_for_sender(
             room_id, event_id, event_map, state_res_store
         )
         event_to_pl[event_id] = pl
 
-        # We yield occasionally when we're working with large data sets to
+        # We await occasionally when we're working with large data sets to
         # ensure that we don't block the reactor loop for too long.
-        if idx % _YIELD_AFTER_ITERATIONS == 0:
-            yield clock.sleep(0)
+        if idx % _AWAIT_AFTER_ITERATIONS == 0:
+            await clock.sleep(0)
 
     def _get_power_order(event_id):
         ev = event_map[event_id]
@@ -378,8 +371,7 @@ def _reverse_topological_power_sort(
     return sorted_events
 
 
-@defer.inlineCallbacks
-def _iterative_auth_checks(
+async def _iterative_auth_checks(
     clock, room_id, room_version, event_ids, base_state, event_map, state_res_store
 ):
     """Sequentially apply auth checks to each event in given list, updating the
@@ -405,7 +397,7 @@ def _iterative_auth_checks(
 
         auth_events = {}
         for aid in event.auth_event_ids():
-            ev = yield _get_event(
+            ev = await _get_event(
                 room_id, aid, event_map, state_res_store, allow_none=True
             )
 
@@ -420,7 +412,7 @@ def _iterative_auth_checks(
         for key in event_auth.auth_types_for_event(event):
             if key in resolved_state:
                 ev_id = resolved_state[key]
-                ev = yield _get_event(room_id, ev_id, event_map, state_res_store)
+                ev = await _get_event(room_id, ev_id, event_map, state_res_store)
 
                 if ev.rejected_reason is None:
                     auth_events[key] = event_map[ev_id]
@@ -438,16 +430,15 @@ def _iterative_auth_checks(
         except AuthError:
             pass
 
-        # We yield occasionally when we're working with large data sets to
+        # We await occasionally when we're working with large data sets to
         # ensure that we don't block the reactor loop for too long.
-        if idx % _YIELD_AFTER_ITERATIONS == 0:
-            yield clock.sleep(0)
+        if idx % _AWAIT_AFTER_ITERATIONS == 0:
+            await clock.sleep(0)
 
     return resolved_state
 
 
-@defer.inlineCallbacks
-def _mainline_sort(
+async def _mainline_sort(
     clock, room_id, event_ids, resolved_power_event_id, event_map, state_res_store
 ):
     """Returns a sorted list of event_ids sorted by mainline ordering based on
@@ -474,21 +465,21 @@ def _mainline_sort(
     idx = 0
     while pl:
         mainline.append(pl)
-        pl_ev = yield _get_event(room_id, pl, event_map, state_res_store)
+        pl_ev = await _get_event(room_id, pl, event_map, state_res_store)
         auth_events = pl_ev.auth_event_ids()
         pl = None
         for aid in auth_events:
-            ev = yield _get_event(
+            ev = await _get_event(
                 room_id, aid, event_map, state_res_store, allow_none=True
             )
             if ev and (ev.type, ev.state_key) == (EventTypes.PowerLevels, ""):
                 pl = aid
                 break
 
-        # We yield occasionally when we're working with large data sets to
+        # We await occasionally when we're working with large data sets to
         # ensure that we don't block the reactor loop for too long.
-        if idx != 0 and idx % _YIELD_AFTER_ITERATIONS == 0:
-            yield clock.sleep(0)
+        if idx != 0 and idx % _AWAIT_AFTER_ITERATIONS == 0:
+            await clock.sleep(0)
 
         idx += 1
 
@@ -498,23 +489,24 @@ def _mainline_sort(
 
     order_map = {}
     for idx, ev_id in enumerate(event_ids, start=1):
-        depth = yield _get_mainline_depth_for_event(
+        depth = await _get_mainline_depth_for_event(
             event_map[ev_id], mainline_map, event_map, state_res_store
         )
         order_map[ev_id] = (depth, event_map[ev_id].origin_server_ts, ev_id)
 
-        # We yield occasionally when we're working with large data sets to
+        # We await occasionally when we're working with large data sets to
         # ensure that we don't block the reactor loop for too long.
-        if idx % _YIELD_AFTER_ITERATIONS == 0:
-            yield clock.sleep(0)
+        if idx % _AWAIT_AFTER_ITERATIONS == 0:
+            await clock.sleep(0)
 
     event_ids.sort(key=lambda ev_id: order_map[ev_id])
 
     return event_ids
 
 
-@defer.inlineCallbacks
-def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_store):
+async def _get_mainline_depth_for_event(
+    event, mainline_map, event_map, state_res_store
+):
     """Get the mainline depths for the given event based on the mainline map
 
     Args:
@@ -541,7 +533,7 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor
         event = None
 
         for aid in auth_events:
-            aev = yield _get_event(
+            aev = await _get_event(
                 room_id, aid, event_map, state_res_store, allow_none=True
             )
             if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""):
@@ -552,8 +544,7 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor
     return 0
 
 
-@defer.inlineCallbacks
-def _get_event(room_id, event_id, event_map, state_res_store, allow_none=False):
+async def _get_event(room_id, event_id, event_map, state_res_store, allow_none=False):
     """Helper function to look up event in event_map, falling back to looking
     it up in the store
 
@@ -569,7 +560,7 @@ def _get_event(room_id, event_id, event_map, state_res_store, allow_none=False):
         Deferred[Optional[FrozenEvent]]
     """
     if event_id not in event_map:
-        events = yield state_res_store.get_events([event_id], allow_rejected=True)
+        events = await state_res_store.get_events([event_id], allow_rejected=True)
         event_map.update(events)
     event = event_map.get(event_id)
 
diff --git a/synapse/storage/data_stores/main/push_rule.py b/synapse/storage/data_stores/main/push_rule.py
index d181488db7..c229248101 100644
--- a/synapse/storage/data_stores/main/push_rule.py
+++ b/synapse/storage/data_stores/main/push_rule.py
@@ -259,7 +259,7 @@ class PushRulesWorkerStore(
             # To do this we set the state_group to a new object as object() != object()
             state_group = object()
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
         result = yield self._bulk_get_push_rules_for_room(
             event.room_id, state_group, current_state_ids, event=event
         )
diff --git a/synapse/storage/data_stores/main/roommember.py b/synapse/storage/data_stores/main/roommember.py
index 29765890ee..a92e401e88 100644
--- a/synapse/storage/data_stores/main/roommember.py
+++ b/synapse/storage/data_stores/main/roommember.py
@@ -497,7 +497,7 @@ class RoomMemberWorkerStore(EventsWorkerStore):
             # To do this we set the state_group to a new object as object() != object()
             state_group = object()
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
         result = yield self._get_joined_users_from_context(
             event.room_id, state_group, current_state_ids, event=event, context=context
         )
diff --git a/synapse/storage/data_stores/main/user_directory.py b/synapse/storage/data_stores/main/user_directory.py
index 6b8130bf0f..942e51fd3a 100644
--- a/synapse/storage/data_stores/main/user_directory.py
+++ b/synapse/storage/data_stores/main/user_directory.py
@@ -198,7 +198,9 @@ class UserDirectoryBackgroundUpdateStore(StateDeltasStore):
                     room_id
                 )
 
-                users_with_profile = yield state.get_current_users_in_room(room_id)
+                users_with_profile = yield defer.ensureDeferred(
+                    state.get_current_users_in_room(room_id)
+                )
                 user_ids = set(users_with_profile)
 
                 # Update each user in the user directory.
diff --git a/synapse/storage/persist_events.py b/synapse/storage/persist_events.py
index fa46041676..78fbdcdee8 100644
--- a/synapse/storage/persist_events.py
+++ b/synapse/storage/persist_events.py
@@ -29,7 +29,6 @@ from synapse.events import FrozenEvent
 from synapse.events.snapshot import EventContext
 from synapse.logging.context import PreserveLoggingContext, make_deferred_yieldable
 from synapse.metrics.background_process_metrics import run_as_background_process
-from synapse.state import StateResolutionStore
 from synapse.storage.data_stores import DataStores
 from synapse.storage.data_stores.main.events import DeltaState
 from synapse.types import StateMap
@@ -648,6 +647,10 @@ class EventsPersistenceStorage(object):
             room_version = await self.main_store.get_room_version_id(room_id)
 
         logger.debug("calling resolve_state_groups from preserve_events")
+
+        # Avoid a circular import.
+        from synapse.state import StateResolutionStore
+
         res = await self._state_resolution_handler.resolve_state_groups(
             room_id,
             room_version,
diff --git a/tests/federation/test_federation_sender.py b/tests/federation/test_federation_sender.py
index 1a9bd5f37d..d1bd18da39 100644
--- a/tests/federation/test_federation_sender.py
+++ b/tests/federation/test_federation_sender.py
@@ -26,21 +26,24 @@ from synapse.rest import admin
 from synapse.rest.client.v1 import login
 from synapse.types import JsonDict, ReadReceipt
 
+from tests.test_utils import make_awaitable
 from tests.unittest import HomeserverTestCase, override_config
 
 
 class FederationSenderReceiptsTestCases(HomeserverTestCase):
     def make_homeserver(self, reactor, clock):
+        mock_state_handler = Mock(spec=["get_current_hosts_in_room"])
+        # Ensure a new Awaitable is created for each call.
+        mock_state_handler.get_current_hosts_in_room.side_effect = lambda room_Id: make_awaitable(
+            ["test", "host2"]
+        )
         return self.setup_test_homeserver(
-            state_handler=Mock(spec=["get_current_hosts_in_room"]),
+            state_handler=mock_state_handler,
             federation_transport_client=Mock(spec=["send_transaction"]),
         )
 
     @override_config({"send_federation": True})
     def test_send_receipts(self):
-        mock_state_handler = self.hs.get_state_handler()
-        mock_state_handler.get_current_hosts_in_room.return_value = ["test", "host2"]
-
         mock_send_transaction = (
             self.hs.get_federation_transport_client().send_transaction
         )
@@ -81,9 +84,6 @@ class FederationSenderReceiptsTestCases(HomeserverTestCase):
     def test_send_receipts_with_backoff(self):
         """Send two receipts in quick succession; the second should be flushed, but
         only after 20ms"""
-        mock_state_handler = self.hs.get_state_handler()
-        mock_state_handler.get_current_hosts_in_room.return_value = ["test", "host2"]
-
         mock_send_transaction = (
             self.hs.get_federation_transport_client().send_transaction
         )
@@ -164,7 +164,6 @@ class FederationSenderDevicesTestCases(HomeserverTestCase):
 
     def make_homeserver(self, reactor, clock):
         return self.setup_test_homeserver(
-            state_handler=Mock(spec=["get_current_hosts_in_room"]),
             federation_transport_client=Mock(spec=["send_transaction"]),
         )
 
@@ -174,10 +173,6 @@ class FederationSenderDevicesTestCases(HomeserverTestCase):
         return c
 
     def prepare(self, reactor, clock, hs):
-        # stub out get_current_hosts_in_room
-        mock_state_handler = hs.get_state_handler()
-        mock_state_handler.get_current_hosts_in_room.return_value = ["test", "host2"]
-
         # stub out get_users_who_share_room_with_user so that it claims that
         # `@user2:host2` is in the room
         def get_users_who_share_room_with_user(user_id):
diff --git a/tests/state/test_v2.py b/tests/state/test_v2.py
index 38f9b423ef..f2955a9c69 100644
--- a/tests/state/test_v2.py
+++ b/tests/state/test_v2.py
@@ -14,6 +14,7 @@
 # limitations under the License.
 
 import itertools
+from typing import List
 
 import attr
 
@@ -432,7 +433,7 @@ class StateTestCase(unittest.TestCase):
                     state_res_store=TestStateResolutionStore(event_map),
                 )
 
-                state_before = self.successResultOf(state_d)
+                state_before = self.successResultOf(defer.ensureDeferred(state_d))
 
             state_after = dict(state_before)
             if fake_event.state_key is not None:
@@ -581,7 +582,7 @@ class SimpleParamStateTestCase(unittest.TestCase):
             state_res_store=TestStateResolutionStore(self.event_map),
         )
 
-        state = self.successResultOf(state_d)
+        state = self.successResultOf(defer.ensureDeferred(state_d))
 
         self.assert_dict(self.expected_combined_state, state)
 
@@ -608,9 +609,11 @@ class TestStateResolutionStore(object):
             Deferred[dict[str, FrozenEvent]]: Dict from event_id to event.
         """
 
-        return {eid: self.event_map[eid] for eid in event_ids if eid in self.event_map}
+        return defer.succeed(
+            {eid: self.event_map[eid] for eid in event_ids if eid in self.event_map}
+        )
 
-    def _get_auth_chain(self, event_ids):
+    def _get_auth_chain(self, event_ids: List[str]) -> List[str]:
         """Gets the full auth chain for a set of events (including rejected
         events).
 
@@ -622,10 +625,10 @@ class TestStateResolutionStore(object):
                presence of rejected events
 
         Args:
-            event_ids (list): The event IDs of the events to fetch the auth
+            event_ids: The event IDs of the events to fetch the auth
                 chain for. Must be state events.
         Returns:
-            Deferred[list[str]]: List of event IDs of the auth chain.
+            List of event IDs of the auth chain.
         """
 
         # Simple DFS for auth chain
@@ -648,4 +651,4 @@ class TestStateResolutionStore(object):
         chains = [frozenset(self._get_auth_chain(a)) for a in auth_sets]
 
         common = set(chains[0]).intersection(*chains[1:])
-        return set(chains[0]).union(*chains[1:]) - common
+        return defer.succeed(set(chains[0]).union(*chains[1:]) - common)
diff --git a/tests/storage/test_room.py b/tests/storage/test_room.py
index b1dceb2918..1d77b4a2d6 100644
--- a/tests/storage/test_room.py
+++ b/tests/storage/test_room.py
@@ -109,7 +109,9 @@ class RoomEventsStoreTestCase(unittest.TestCase):
             etype=EventTypes.Name, name=name, content={"name": name}, depth=1
         )
 
-        state = yield self.store.get_current_state(room_id=self.room.to_string())
+        state = yield defer.ensureDeferred(
+            self.store.get_current_state(room_id=self.room.to_string())
+        )
 
         self.assertEquals(1, len(state))
         self.assertObjectHasAttributes(
@@ -125,7 +127,9 @@ class RoomEventsStoreTestCase(unittest.TestCase):
             etype=EventTypes.Topic, topic=topic, content={"topic": topic}, depth=1
         )
 
-        state = yield self.store.get_current_state(room_id=self.room.to_string())
+        state = yield defer.ensureDeferred(
+            self.store.get_current_state(room_id=self.room.to_string())
+        )
 
         self.assertEquals(1, len(state))
         self.assertObjectHasAttributes(
diff --git a/tests/test_state.py b/tests/test_state.py
index 66f22f6813..4858e8fc59 100644
--- a/tests/test_state.py
+++ b/tests/test_state.py
@@ -97,17 +97,19 @@ class StateGroupStore(object):
 
         self._group_to_state[state_group] = dict(current_state_ids)
 
-        return state_group
+        return defer.succeed(state_group)
 
     def get_events(self, event_ids, **kwargs):
-        return {
-            e_id: self._event_id_to_event[e_id]
-            for e_id in event_ids
-            if e_id in self._event_id_to_event
-        }
+        return defer.succeed(
+            {
+                e_id: self._event_id_to_event[e_id]
+                for e_id in event_ids
+                if e_id in self._event_id_to_event
+            }
+        )
 
     def get_state_group_delta(self, name):
-        return None, None
+        return defer.succeed((None, None))
 
     def register_events(self, events):
         for e in events:
@@ -120,7 +122,7 @@ class StateGroupStore(object):
         self._event_to_state_group[event_id] = state_group
 
     def get_room_version_id(self, room_id):
-        return RoomVersions.V1.identifier
+        return defer.succeed(RoomVersions.V1.identifier)
 
 
 class DictObj(dict):
@@ -202,7 +204,9 @@ class StateTestCase(unittest.TestCase):
         context_store = {}  # type: dict[str, EventContext]
 
         for event in graph.walk():
-            context = yield self.state.compute_event_context(event)
+            context = yield defer.ensureDeferred(
+                self.state.compute_event_context(event)
+            )
             self.store.register_event_context(event, context)
             context_store[event.event_id] = context
 
@@ -244,7 +248,9 @@ class StateTestCase(unittest.TestCase):
         context_store = {}
 
         for event in graph.walk():
-            context = yield self.state.compute_event_context(event)
+            context = yield defer.ensureDeferred(
+                self.state.compute_event_context(event)
+            )
             self.store.register_event_context(event, context)
             context_store[event.event_id] = context
 
@@ -300,7 +306,9 @@ class StateTestCase(unittest.TestCase):
         context_store = {}
 
         for event in graph.walk():
-            context = yield self.state.compute_event_context(event)
+            context = yield defer.ensureDeferred(
+                self.state.compute_event_context(event)
+            )
             self.store.register_event_context(event, context)
             context_store[event.event_id] = context
 
@@ -373,7 +381,9 @@ class StateTestCase(unittest.TestCase):
         context_store = {}
 
         for event in graph.walk():
-            context = yield self.state.compute_event_context(event)
+            context = yield defer.ensureDeferred(
+                self.state.compute_event_context(event)
+            )
             self.store.register_event_context(event, context)
             context_store[event.event_id] = context
 
@@ -411,12 +421,14 @@ class StateTestCase(unittest.TestCase):
             create_event(type="test2", state_key=""),
         ]
 
-        context = yield self.state.compute_event_context(event, old_state=old_state)
+        context = yield defer.ensureDeferred(
+            self.state.compute_event_context(event, old_state=old_state)
+        )
 
         prev_state_ids = yield context.get_prev_state_ids()
         self.assertCountEqual((e.event_id for e in old_state), prev_state_ids.values())
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
         self.assertCountEqual(
             (e.event_id for e in old_state), current_state_ids.values()
         )
@@ -434,12 +446,14 @@ class StateTestCase(unittest.TestCase):
             create_event(type="test2", state_key=""),
         ]
 
-        context = yield self.state.compute_event_context(event, old_state=old_state)
+        context = yield defer.ensureDeferred(
+            self.state.compute_event_context(event, old_state=old_state)
+        )
 
         prev_state_ids = yield context.get_prev_state_ids()
         self.assertCountEqual((e.event_id for e in old_state), prev_state_ids.values())
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
         self.assertCountEqual(
             (e.event_id for e in old_state + [event]), current_state_ids.values()
         )
@@ -462,7 +476,7 @@ class StateTestCase(unittest.TestCase):
             create_event(type="test2", state_key=""),
         ]
 
-        group_name = self.store.store_state_group(
+        group_name = yield self.store.store_state_group(
             prev_event_id,
             event.room_id,
             None,
@@ -471,9 +485,9 @@ class StateTestCase(unittest.TestCase):
         )
         self.store.register_event_id_state_group(prev_event_id, group_name)
 
-        context = yield self.state.compute_event_context(event)
+        context = yield defer.ensureDeferred(self.state.compute_event_context(event))
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
 
         self.assertEqual(
             {e.event_id for e in old_state}, set(current_state_ids.values())
@@ -494,7 +508,7 @@ class StateTestCase(unittest.TestCase):
             create_event(type="test2", state_key=""),
         ]
 
-        group_name = self.store.store_state_group(
+        group_name = yield self.store.store_state_group(
             prev_event_id,
             event.room_id,
             None,
@@ -503,7 +517,7 @@ class StateTestCase(unittest.TestCase):
         )
         self.store.register_event_id_state_group(prev_event_id, group_name)
 
-        context = yield self.state.compute_event_context(event)
+        context = yield defer.ensureDeferred(self.state.compute_event_context(event))
 
         prev_state_ids = yield context.get_prev_state_ids()
 
@@ -544,7 +558,7 @@ class StateTestCase(unittest.TestCase):
             event, prev_event_id1, old_state_1, prev_event_id2, old_state_2
         )
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
 
         self.assertEqual(len(current_state_ids), 6)
 
@@ -586,7 +600,7 @@ class StateTestCase(unittest.TestCase):
             event, prev_event_id1, old_state_1, prev_event_id2, old_state_2
         )
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
 
         self.assertEqual(len(current_state_ids), 6)
 
@@ -641,7 +655,7 @@ class StateTestCase(unittest.TestCase):
             event, prev_event_id1, old_state_1, prev_event_id2, old_state_2
         )
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
 
         self.assertEqual(old_state_2[3].event_id, current_state_ids[("test1", "1")])
 
@@ -669,14 +683,15 @@ class StateTestCase(unittest.TestCase):
             event, prev_event_id1, old_state_1, prev_event_id2, old_state_2
         )
 
-        current_state_ids = yield context.get_current_state_ids()
+        current_state_ids = yield defer.ensureDeferred(context.get_current_state_ids())
 
         self.assertEqual(old_state_1[3].event_id, current_state_ids[("test1", "1")])
 
+    @defer.inlineCallbacks
     def _get_context(
         self, event, prev_event_id_1, old_state_1, prev_event_id_2, old_state_2
     ):
-        sg1 = self.store.store_state_group(
+        sg1 = yield self.store.store_state_group(
             prev_event_id_1,
             event.room_id,
             None,
@@ -685,7 +700,7 @@ class StateTestCase(unittest.TestCase):
         )
         self.store.register_event_id_state_group(prev_event_id_1, sg1)
 
-        sg2 = self.store.store_state_group(
+        sg2 = yield self.store.store_state_group(
             prev_event_id_2,
             event.room_id,
             None,
@@ -694,4 +709,5 @@ class StateTestCase(unittest.TestCase):
         )
         self.store.register_event_id_state_group(prev_event_id_2, sg2)
 
-        return self.state.compute_event_context(event)
+        result = yield defer.ensureDeferred(self.state.compute_event_context(event))
+        return result
diff --git a/tests/test_utils/__init__.py b/tests/test_utils/__init__.py
index 7b345b03bb..508aeba078 100644
--- a/tests/test_utils/__init__.py
+++ b/tests/test_utils/__init__.py
@@ -17,7 +17,7 @@
 """
 Utilities for running the unit tests
 """
-from typing import Awaitable, TypeVar
+from typing import Any, Awaitable, TypeVar
 
 TV = TypeVar("TV")
 
@@ -36,3 +36,8 @@ def get_awaitable_result(awaitable: Awaitable[TV]) -> TV:
 
     # if next didn't raise, the awaitable hasn't completed.
     raise Exception("awaitable has not yet completed")
+
+
+async def make_awaitable(result: Any):
+    """Create an awaitable that just returns a result."""
+    return result
-- 
cgit 1.5.1


From 2c1b9d676322fad8cb57c92f97f81393bcfcbe56 Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Wed, 29 Jul 2020 23:22:13 +0100
Subject: Update worker docs with recent enhancements  (#7969)

---
 changelog.d/7969.doc                               |   1 +
 docs/sample_config.yaml                            |  54 +++
 docs/synctl_workers.md                             |  32 ++
 docs/workers.md                                    | 459 +++++++++++----------
 synapse/app/generic_worker.py                      |   6 +-
 synapse/config/federation.py                       |  12 +-
 synapse/config/homeserver.py                       |   2 +-
 synapse/config/logger.py                           |   2 +-
 synapse/config/redis.py                            |  23 +-
 synapse/config/workers.py                          |  49 ++-
 synapse/federation/send_queue.py                   |   2 +-
 synapse/federation/sender/__init__.py              |   2 +-
 synapse/federation/sender/per_destination_queue.py |   2 +-
 synapse/storage/data_stores/main/stream.py         |   2 +-
 14 files changed, 413 insertions(+), 235 deletions(-)
 create mode 100644 changelog.d/7969.doc
 create mode 100644 docs/synctl_workers.md

(limited to 'synapse/federation')

diff --git a/changelog.d/7969.doc b/changelog.d/7969.doc
new file mode 100644
index 0000000000..68d2ed5fad
--- /dev/null
+++ b/changelog.d/7969.doc
@@ -0,0 +1 @@
+Update worker docs with latest enhancements.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 3227294e0b..b21e36bb6d 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -2398,3 +2398,57 @@ opentracing:
     #
     #  logging:
     #    false
+
+
+## Workers ##
+
+# Disables sending of outbound federation transactions on the main process.
+# Uncomment if using a federation sender worker.
+#
+#send_federation: false
+
+# It is possible to run multiple federation sender workers, in which case the
+# work is balanced across them.
+#
+# This configuration must be shared between all federation sender workers, and if
+# changed all federation sender workers must be stopped at the same time and then
+# started, to ensure that all instances are running with the same config (otherwise
+# events may be dropped).
+#
+#federation_sender_instances:
+#  - federation_sender1
+
+# When using workers this should be a map from `worker_name` to the
+# HTTP replication listener of the worker, if configured.
+#
+#instance_map:
+#  worker1:
+#    host: localhost
+#    port: 8034
+
+# Experimental: When using workers you can define which workers should
+# handle event persistence and typing notifications. Any worker
+# specified here must also be in the `instance_map`.
+#
+#stream_writers:
+#  events: worker1
+#  typing: worker1
+
+
+# Configuration for Redis when using workers. This *must* be enabled when
+# using workers (unless using old style direct TCP configuration).
+#
+redis:
+  # Uncomment the below to enable Redis support.
+  #
+  #enabled: true
+
+  # Optional host and port to use to connect to redis. Defaults to
+  # localhost and 6379
+  #
+  #host: localhost
+  #port: 6379
+
+  # Optional password if configured on the Redis instance
+  #
+  #password: <secret_password>
diff --git a/docs/synctl_workers.md b/docs/synctl_workers.md
new file mode 100644
index 0000000000..8da4a31852
--- /dev/null
+++ b/docs/synctl_workers.md
@@ -0,0 +1,32 @@
+### Using synctl with workers
+
+If you want to use `synctl` to manage your synapse processes, you will need to
+create an an additional configuration file for the main synapse process. That
+configuration should look like this:
+
+```yaml
+worker_app: synapse.app.homeserver
+```
+
+Additionally, each worker app must be configured with the name of a "pid file",
+to which it will write its process ID when it starts. For example, for a
+synchrotron, you might write:
+
+```yaml
+worker_pid_file: /home/matrix/synapse/worker1.pid
+```
+
+Finally, to actually run your worker-based synapse, you must pass synctl the `-a`
+commandline option to tell it to operate on all the worker configurations found
+in the given directory, e.g.:
+
+    synctl -a $CONFIG/workers start
+
+Currently one should always restart all workers when restarting or upgrading
+synapse, unless you explicitly know it's safe not to.  For instance, restarting
+synapse without restarting all the synchrotrons may result in broken typing
+notifications.
+
+To manipulate a specific worker, you pass the -w option to synctl:
+
+    synctl -w $CONFIG/workers/worker1.yaml restart
diff --git a/docs/workers.md b/docs/workers.md
index f4cbbc0400..38bd758e57 100644
--- a/docs/workers.md
+++ b/docs/workers.md
@@ -16,69 +16,106 @@ workers only work with PostgreSQL-based Synapse deployments. SQLite should only
 be used for demo purposes and any admin considering workers should already be
 running PostgreSQL.
 
-## Master/worker communication
+## Main process/worker communication
 
-The workers communicate with the master process via a Synapse-specific protocol
-called 'replication' (analogous to MySQL- or Postgres-style database
-replication) which feeds a stream of relevant data from the master to the
-workers so they can be kept in sync with the master process and database state.
+The processes communicate with each other via a Synapse-specific protocol called
+'replication' (analogous to MySQL- or Postgres-style database replication) which
+feeds streams of newly written data between processes so they can be kept in
+sync with the database state.
 
-Additionally, workers may make HTTP requests to the master, to send information
-in the other direction. Typically this is used for operations which need to
-wait for a reply - such as sending an event.
+Additionally, processes may make HTTP requests to each other. Typically this is
+used for operations which need to wait for a reply - such as sending an event.
 
-## Configuration
+As of Synapse v1.13.0, it is possible to configure Synapse to send replication
+via a [Redis pub/sub channel](https://redis.io/topics/pubsub), and is now the
+recommended way of configuring replication. This is an alternative to the old
+direct TCP connections to the main process: rather than all the workers
+connecting to the main process, all the workers and the main process connect to
+Redis, which relays replication commands between processes. This can give a
+significant cpu saving on the main process and will be a prerequisite for
+upcoming performance improvements.
+
+(See the [Architectural diagram](#architectural-diagram) section at the end for
+a visualisation of what this looks like)
+
+
+## Setting up workers
+
+A Redis server is required to manage the communication between the processes.
+(The older direct TCP connections are now deprecated.) The Redis server
+should be installed following the normal procedure for your distribution (e.g.
+`apt install redis-server` on Debian). It is safe to use an existing Redis
+deployment if you have one.
+
+Once installed, check that Redis is running and accessible from the host running
+Synapse, for example by executing `echo PING | nc -q1 localhost 6379` and seeing
+a response of `+PONG`.
+
+The appropriate dependencies must also be installed for Synapse. If using a
+virtualenv, these can be installed with:
+
+```sh
+pip install matrix-synapse[redis]
+```
+
+Note that these dependencies are included when synapse is installed with `pip
+install matrix-synapse[all]`. They are also included in the debian packages from
+`matrix.org` and in the docker images at
+https://hub.docker.com/r/matrixdotorg/synapse/.
 
 To make effective use of the workers, you will need to configure an HTTP
 reverse-proxy such as nginx or haproxy, which will direct incoming requests to
-the correct worker, or to the main synapse instance. Note that this includes
-requests made to the federation port. See [reverse_proxy.md](reverse_proxy.md)
+the correct worker, or to the main synapse instance. See [reverse_proxy.md](reverse_proxy.md)
 for information on setting up a reverse proxy.
 
-To enable workers, you need to add *two* replication listeners to the
-main Synapse configuration file (`homeserver.yaml`). For example:
+To enable workers you should create a configuration file for each worker
+process. Each worker configuration file inherits the configuration of the shared
+homeserver configuration file.  You can then override configuration specific to
+that worker, e.g. the HTTP listener that it provides (if any); logging
+configuration; etc.  You should minimise the number of overrides though to
+maintain a usable config.
+
+Next you need to add both a HTTP replication listener and redis config to the
+shared Synapse configuration file (`homeserver.yaml`). For example:
 
 ```yaml
+# extend the existing `listeners` section. This defines the ports that the
+# main process will listen on.
 listeners:
-  # The TCP replication port
-  - port: 9092
-    bind_address: '127.0.0.1'
-    type: replication
-
   # The HTTP replication port
   - port: 9093
     bind_address: '127.0.0.1'
     type: http
     resources:
      - names: [replication]
+
+redis:
+    enabled: true
 ```
 
-Under **no circumstances** should these replication API listeners be exposed to
-the public internet; they have no authentication and are unencrypted.
+See the sample config for the full documentation of each option.
 
-You should then create a set of configs for the various worker processes.  Each
-worker configuration file inherits the configuration of the main homeserver
-configuration file.  You can then override configuration specific to that
-worker, e.g. the HTTP listener that it provides (if any); logging
-configuration; etc.  You should minimise the number of overrides though to
-maintain a usable config.
+Under **no circumstances** should the replication listener be exposed to the
+public internet; it has no authentication and is unencrypted.
 
 In the config file for each worker, you must specify the type of worker
-application (`worker_app`). The currently available worker applications are
-listed below. You must also specify the replication endpoints that it should
-talk to on the main synapse process.  `worker_replication_host` should specify
-the host of the main synapse, `worker_replication_port` should point to the TCP
-replication listener port and `worker_replication_http_port` should point to
-the HTTP replication port.
+application (`worker_app`), and you should specify a unqiue name for the worker
+(`worker_name`). The currently available worker applications are listed below.
+You must also specify the HTTP replication endpoint that it should talk to on
+the main synapse process.  `worker_replication_host` should specify the host of
+the main synapse and `worker_replication_http_port` should point to the HTTP
+replication port. If the worker will handle HTTP requests then the
+`worker_listeners` option should be set with a `http` listener, in the same way
+as the `listeners` option in the shared config.
 
 For example:
 
 ```yaml
-worker_app: synapse.app.synchrotron
+worker_app: synapse.app.generic_worker
+worker_name: worker1
 
-# The replication listener on the synapse to talk to.
+# The replication listener on the main synapse process.
 worker_replication_host: 127.0.0.1
-worker_replication_port: 9092
 worker_replication_http_port: 9093
 
 worker_listeners:
@@ -87,13 +124,14 @@ worker_listeners:
    resources:
      - names:
        - client
+       - federation
 
-worker_log_config: /home/matrix/synapse/config/synchrotron_log_config.yaml
+worker_log_config: /home/matrix/synapse/config/worker1_log_config.yaml
 ```
 
-...is a full configuration for a synchrotron worker instance, which will expose a
-plain HTTP `/sync` endpoint on port 8083 separately from the `/sync` endpoint provided
-by the main synapse.
+...is a full configuration for a generic worker instance, which will expose a
+plain HTTP endpoint on port 8083 separately serving various endpoints, e.g.
+`/sync`, which are listed below.
 
 Obviously you should configure your reverse-proxy to route the relevant
 endpoints to the worker (`localhost:8083` in the above example).
@@ -102,127 +140,24 @@ Finally, you need to start your worker processes. This can be done with either
 `synctl` or your distribution's preferred service manager such as `systemd`. We
 recommend the use of `systemd` where available: for information on setting up
 `systemd` to start synapse workers, see
-[systemd-with-workers](systemd-with-workers). To use `synctl`, see below.
+[systemd-with-workers](systemd-with-workers). To use `synctl`, see
+[synctl_workers.md](synctl_workers.md).
 
-### **Experimental** support for replication over redis
-
-As of Synapse v1.13.0, it is possible to configure Synapse to send replication
-via a [Redis pub/sub channel](https://redis.io/topics/pubsub). This is an
-alternative to direct TCP connections to the master: rather than all the
-workers connecting to the master, all the workers and the master connect to
-Redis, which relays replication commands between processes. This can give a
-significant cpu saving on the master and will be a prerequisite for upcoming
-performance improvements.
-
-Note that this support is currently experimental; you may experience lost
-messages and similar problems! It is strongly recommended that admins setting
-up workers for the first time use direct TCP replication as above.
-
-To configure Synapse to use Redis:
-
-1. Install Redis following the normal procedure for your distribution - for
-   example, on Debian, `apt install redis-server`. (It is safe to use an
-   existing Redis deployment if you have one: we use a pub/sub stream named
-   according to the `server_name` of your synapse server.)
-2. Check Redis is running and accessible: you should be able to `echo PING | nc -q1
-   localhost 6379` and get a response of `+PONG`.
-3. Install the python prerequisites. If you installed synapse into a
-   virtualenv, this can be done with:
-   ```sh
-   pip install matrix-synapse[redis]
-   ```
-   The debian packages from matrix.org already include the required
-   dependencies.
-4. Add config to the shared configuration (`homeserver.yaml`):
-    ```yaml
-    redis:
-      enabled: true
-    ```
-    Optional parameters which can go alongside `enabled` are `host`, `port`,
-    `password`. Normally none of these are required.
-5. Restart master and all workers.
-
-Once redis replication is in use, `worker_replication_port` is redundant and
-can be removed from the worker configuration files. Similarly, the
-configuration for the `listener` for the TCP replication port can be removed
-from the main configuration file. Note that the HTTP replication port is
-still required.
-
-### Using synctl
-
-If you want to use `synctl` to manage your synapse processes, you will need to
-create an an additional configuration file for the master synapse process. That
-configuration should look like this:
-
-```yaml
-worker_app: synapse.app.homeserver
-```
-
-Additionally, each worker app must be configured with the name of a "pid file",
-to which it will write its process ID when it starts. For example, for a
-synchrotron, you might write:
-
-```yaml
-worker_pid_file: /home/matrix/synapse/synchrotron.pid
-```
-
-Finally, to actually run your worker-based synapse, you must pass synctl the `-a`
-commandline option to tell it to operate on all the worker configurations found
-in the given directory, e.g.:
-
-    synctl -a $CONFIG/workers start
-
-Currently one should always restart all workers when restarting or upgrading
-synapse, unless you explicitly know it's safe not to.  For instance, restarting
-synapse without restarting all the synchrotrons may result in broken typing
-notifications.
-
-To manipulate a specific worker, you pass the -w option to synctl:
-
-    synctl -w $CONFIG/workers/synchrotron.yaml restart
 
 ## Available worker applications
 
-### `synapse.app.pusher`
-
-Handles sending push notifications to sygnal and email. Doesn't handle any
-REST endpoints itself, but you should set `start_pushers: False` in the
-shared configuration file to stop the main synapse sending these notifications.
-
-Note this worker cannot be load-balanced: only one instance should be active.
-
-### `synapse.app.synchrotron`
+### `synapse.app.generic_worker`
 
-The synchrotron handles `sync` requests from clients. In particular, it can
-handle REST endpoints matching the following regular expressions:
+This worker can handle API requests matching the following regular
+expressions:
 
+    # Sync requests
     ^/_matrix/client/(v2_alpha|r0)/sync$
     ^/_matrix/client/(api/v1|v2_alpha|r0)/events$
     ^/_matrix/client/(api/v1|r0)/initialSync$
     ^/_matrix/client/(api/v1|r0)/rooms/[^/]+/initialSync$
 
-The above endpoints should all be routed to the synchrotron worker by the
-reverse-proxy configuration.
-
-It is possible to run multiple instances of the synchrotron to scale
-horizontally. In this case the reverse-proxy should be configured to
-load-balance across the instances, though it will be more efficient if all
-requests from a particular user are routed to a single instance. Extracting
-a userid from the access token is currently left as an exercise for the reader.
-
-### `synapse.app.appservice`
-
-Handles sending output traffic to Application Services. Doesn't handle any
-REST endpoints itself, but you should set `notify_appservices: False` in the
-shared configuration file to stop the main synapse sending these notifications.
-
-Note this worker cannot be load-balanced: only one instance should be active.
-
-### `synapse.app.federation_reader`
-
-Handles a subset of federation endpoints. In particular, it can handle REST
-endpoints matching the following regular expressions:
-
+    # Federation requests
     ^/_matrix/federation/v1/event/
     ^/_matrix/federation/v1/state/
     ^/_matrix/federation/v1/state_ids/
@@ -242,40 +177,145 @@ endpoints matching the following regular expressions:
     ^/_matrix/federation/v1/event_auth/
     ^/_matrix/federation/v1/exchange_third_party_invite/
     ^/_matrix/federation/v1/user/devices/
-    ^/_matrix/federation/v1/send/
     ^/_matrix/federation/v1/get_groups_publicised$
     ^/_matrix/key/v2/query
 
+    # Inbound federation transaction request
+    ^/_matrix/federation/v1/send/
+
+    # Client API requests
+    ^/_matrix/client/(api/v1|r0|unstable)/publicRooms$
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/joined_members$
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/context/.*$
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/members$
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/state$
+    ^/_matrix/client/(api/v1|r0|unstable)/account/3pid$
+    ^/_matrix/client/(api/v1|r0|unstable)/keys/query$
+    ^/_matrix/client/(api/v1|r0|unstable)/keys/changes$
+    ^/_matrix/client/versions$
+    ^/_matrix/client/(api/v1|r0|unstable)/voip/turnServer$
+    ^/_matrix/client/(api/v1|r0|unstable)/joined_groups$
+    ^/_matrix/client/(api/v1|r0|unstable)/publicised_groups$
+    ^/_matrix/client/(api/v1|r0|unstable)/publicised_groups/
+
+    # Registration/login requests
+    ^/_matrix/client/(api/v1|r0|unstable)/login$
+    ^/_matrix/client/(r0|unstable)/register$
+    ^/_matrix/client/(r0|unstable)/auth/.*/fallback/web$
+
+    # Event sending requests
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/send
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/state/
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/(join|invite|leave|ban|unban|kick)$
+    ^/_matrix/client/(api/v1|r0|unstable)/join/
+    ^/_matrix/client/(api/v1|r0|unstable)/profile/
+
+
 Additionally, the following REST endpoints can be handled for GET requests:
 
     ^/_matrix/federation/v1/groups/
 
-The above endpoints should all be routed to the federation_reader worker by the
-reverse-proxy configuration.
+Pagination requests can also be handled, but all requests for a given
+room must be routed to the same instance. Additionally, care must be taken to
+ensure that the purge history admin API is not used while pagination requests
+for the room are in flight:
+
+    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/messages$
+
+Note that a HTTP listener with `client` and `federation` resources must be
+configured in the `worker_listeners` option in the worker config.
+
+
+#### Load balancing
+
+It is possible to run multiple instances of this worker app, with incoming requests
+being load-balanced between them by the reverse-proxy. However, different endpoints
+have different characteristics and so admins
+may wish to run multiple groups of workers handling different endpoints so that
+load balancing can be done in different ways.
+
+For `/sync` and `/initialSync` requests it will be more efficient if all
+requests from a particular user are routed to a single instance. Extracting a
+user ID from the access token or `Authorization` header is currently left as an
+exercise for the reader. Admins may additionally wish to separate out `/sync`
+requests that have a `since` query parameter from those that don't (and
+`/initialSync`), as requests that don't are known as "initial sync" that happens
+when a user logs in on a new device and can be *very* resource intensive, so
+isolating these requests will stop them from interfering with other users ongoing
+syncs.
+
+Federation and client requests can be balanced via simple round robin.
 
-The `^/_matrix/federation/v1/send/` endpoint must only be handled by a single
-instance.
+The inbound federation transaction request `^/_matrix/federation/v1/send/`
+should be balanced by source IP so that transactions from the same remote server
+go to the same process.
 
-Note that `federation` must be added to the listener resources in the worker config:
+Registration/login requests can be handled separately purely to help ensure that
+unexpected load doesn't affect new logins and sign ups.
+
+Finally, event sending requests can be balanced by the room ID in the URI (or
+the full URI, or even just round robin), the room ID is the path component after
+`/rooms/`. If there is a large bridge connected that is sending or may send lots
+of events, then a dedicated set of workers can be provisioned to limit the
+effects of bursts of events from that bridge on events sent by normal users.
+
+#### Stream writers
+
+Additionally, there is *experimental* support for moving writing of specific
+streams (such as events) off of the main process to a particular worker. (This
+is only supported with Redis-based replication.)
+
+Currently support streams are `events` and `typing`.
+
+To enable this, the worker must have a HTTP replication listener configured,
+have a `worker_name` and be listed in the `instance_map` config. For example to
+move event persistence off to a dedicated worker, the shared configuration would
+include:
 
 ```yaml
-worker_app: synapse.app.federation_reader
-...
-worker_listeners:
- - type: http
-   port: <port>
-   resources:
-     - names:
-       - federation
+instance_map:
+    event_persister1:
+        host: localhost
+        port: 8034
+
+streams_writers:
+    events: event_persister1
 ```
 
+
+### `synapse.app.pusher`
+
+Handles sending push notifications to sygnal and email. Doesn't handle any
+REST endpoints itself, but you should set `start_pushers: False` in the
+shared configuration file to stop the main synapse sending push notifications.
+
+Note this worker cannot be load-balanced: only one instance should be active.
+
+### `synapse.app.appservice`
+
+Handles sending output traffic to Application Services. Doesn't handle any
+REST endpoints itself, but you should set `notify_appservices: False` in the
+shared configuration file to stop the main synapse sending appservice notifications.
+
+Note this worker cannot be load-balanced: only one instance should be active.
+
+
 ### `synapse.app.federation_sender`
 
 Handles sending federation traffic to other servers. Doesn't handle any
 REST endpoints itself, but you should set `send_federation: False` in the
 shared configuration file to stop the main synapse sending this traffic.
 
-Note this worker cannot be load-balanced: only one instance should be active.
+If running multiple federation senders then you must list each
+instance in the `federation_sender_instances` option by their `worker_name`.
+All instances must be stopped and started when adding or removing instances.
+For example:
+
+```yaml
+federation_sender_instances:
+    - federation_sender1
+    - federation_sender2
+```
 
 ### `synapse.app.media_repository`
 
@@ -314,46 +354,6 @@ and you must configure a single instance to run the background tasks, e.g.:
     media_instance_running_background_jobs: "media-repository-1"
 ```
 
-### `synapse.app.client_reader`
-
-Handles client API endpoints. It can handle REST endpoints matching the
-following regular expressions:
-
-    ^/_matrix/client/(api/v1|r0|unstable)/publicRooms$
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/joined_members$
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/context/.*$
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/members$
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/state$
-    ^/_matrix/client/(api/v1|r0|unstable)/login$
-    ^/_matrix/client/(api/v1|r0|unstable)/account/3pid$
-    ^/_matrix/client/(api/v1|r0|unstable)/keys/query$
-    ^/_matrix/client/(api/v1|r0|unstable)/keys/changes$
-    ^/_matrix/client/versions$
-    ^/_matrix/client/(api/v1|r0|unstable)/voip/turnServer$
-    ^/_matrix/client/(api/v1|r0|unstable)/joined_groups$
-    ^/_matrix/client/(api/v1|r0|unstable)/publicised_groups$
-    ^/_matrix/client/(api/v1|r0|unstable)/publicised_groups/
-
-Additionally, the following REST endpoints can be handled for GET requests:
-
-    ^/_matrix/client/(api/v1|r0|unstable)/pushrules/.*$
-    ^/_matrix/client/(api/v1|r0|unstable)/groups/.*$
-    ^/_matrix/client/(api/v1|r0|unstable)/user/[^/]*/account_data/
-    ^/_matrix/client/(api/v1|r0|unstable)/user/[^/]*/rooms/[^/]*/account_data/
-
-Additionally, the following REST endpoints can be handled, but all requests must
-be routed to the same instance:
-
-    ^/_matrix/client/(r0|unstable)/register$
-    ^/_matrix/client/(r0|unstable)/auth/.*/fallback/web$
-
-Pagination requests can also be handled, but all requests with the same path
-room must be routed to the same instance. Additionally, care must be taken to
-ensure that the purge history admin API is not used while pagination requests
-for the room are in flight:
-
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/messages$
-
 ### `synapse.app.user_dir`
 
 Handles searches in the user directory. It can handle REST endpoints matching
@@ -388,15 +388,48 @@ file. For example:
 
     worker_main_http_uri: http://127.0.0.1:8008
 
-### `synapse.app.event_creator`
+### Historical apps
 
-Handles some event creation. It can handle REST endpoints matching:
+*Note:* Historically there used to be more apps, however they have been
+amalgamated into a single `synapse.app.generic_worker` app. The remaining apps
+are ones that do specific processing unrelated to requests, e.g. the `pusher`
+that handles sending out push notifications for new events. The intention is for
+all these to be folded into the `generic_worker` app and to use config to define
+which processes handle the various proccessing such as push notifications.
 
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/send
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/state/
-    ^/_matrix/client/(api/v1|r0|unstable)/rooms/.*/(join|invite|leave|ban|unban|kick)$
-    ^/_matrix/client/(api/v1|r0|unstable)/join/
-    ^/_matrix/client/(api/v1|r0|unstable)/profile/
 
-It will create events locally and then send them on to the main synapse
-instance to be persisted and handled.
+## Architectural diagram
+
+The following shows an example setup using Redis and a reverse proxy:
+
+```
+                     Clients & Federation
+                              |
+                              v
+                        +-----------+
+                        |           |
+                        |  Reverse  |
+                        |  Proxy    |
+                        |           |
+                        +-----------+
+                            | | |
+                            | | | HTTP requests
+        +-------------------+ | +-----------+
+        |                 +---+             |
+        |                 |                 |
+        v                 v                 v
++--------------+  +--------------+  +--------------+  +--------------+
+|   Main       |  |   Generic    |  |   Generic    |  |  Event       |
+|   Process    |  |   Worker 1   |  |   Worker 2   |  |  Persister   |
++--------------+  +--------------+  +--------------+  +--------------+
+      ^    ^          |   ^   |         |   ^   |          ^    ^
+      |    |          |   |   |         |   |   |          |    |
+      |    |          |   |   |  HTTP   |   |   |          |    |
+      |    +----------+<--|---|---------+   |   |          |    |
+      |                   |   +-------------|-->+----------+    |
+      |                   |                 |                   |
+      |                   |                 |                   |
+      v                   v                 v                   v
+====================================================================
+                                                         Redis pub/sub channel
+```
diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index ec0dbddb8c..5841454c9a 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -940,7 +940,7 @@ def start(config_options):
         config.server.update_user_directory = False
 
     if config.worker_app == "synapse.app.federation_sender":
-        if config.federation.send_federation:
+        if config.worker.send_federation:
             sys.stderr.write(
                 "\nThe send_federation must be disabled in the main synapse process"
                 "\nbefore they can be run in a separate worker."
@@ -950,10 +950,10 @@ def start(config_options):
             sys.exit(1)
 
         # Force the pushers to start since they will be disabled in the main config
-        config.federation.send_federation = True
+        config.worker.send_federation = True
     else:
         # For other worker types we force this to off.
-        config.federation.send_federation = False
+        config.worker.send_federation = False
 
     synapse.events.USE_FROZEN_DICTS = config.use_frozen_dicts
 
diff --git a/synapse/config/federation.py b/synapse/config/federation.py
index 82ff9664de..2c77d8f85b 100644
--- a/synapse/config/federation.py
+++ b/synapse/config/federation.py
@@ -17,23 +17,13 @@ from typing import Optional
 
 from netaddr import IPSet
 
-from ._base import Config, ConfigError, ShardedWorkerHandlingConfig
+from ._base import Config, ConfigError
 
 
 class FederationConfig(Config):
     section = "federation"
 
     def read_config(self, config, **kwargs):
-        # Whether to send federation traffic out in this process. This only
-        # applies to some federation traffic, and so shouldn't be used to
-        # "disable" federation
-        self.send_federation = config.get("send_federation", True)
-
-        federation_sender_instances = config.get("federation_sender_instances") or []
-        self.federation_shard_config = ShardedWorkerHandlingConfig(
-            federation_sender_instances
-        )
-
         # FIXME: federation_domain_whitelist needs sytests
         self.federation_domain_whitelist = None  # type: Optional[dict]
         federation_domain_whitelist = config.get("federation_domain_whitelist", None)
diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index 8e93d31394..556e291495 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -78,7 +78,6 @@ class HomeServerConfig(RootConfig):
         JWTConfig,
         PasswordConfig,
         EmailConfig,
-        WorkerConfig,
         PasswordAuthProviderConfig,
         PushConfig,
         SpamCheckerConfig,
@@ -91,6 +90,7 @@ class HomeServerConfig(RootConfig):
         RoomDirectoryConfig,
         ThirdPartyRulesConfig,
         TracerConfig,
+        WorkerConfig,
         RedisConfig,
         FederationConfig,
     ]
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 49f6c32beb..dd775a97e8 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -214,7 +214,7 @@ def setup_logging(
     Set up the logging subsystem.
 
     Args:
-        config (LoggingConfig | synapse.config.workers.WorkerConfig):
+        config (LoggingConfig | synapse.config.worker.WorkerConfig):
             configuration data
 
         use_worker_options (bool): True to use the 'worker_log_config' option
diff --git a/synapse/config/redis.py b/synapse/config/redis.py
index d5d3ca1c9e..1373302335 100644
--- a/synapse/config/redis.py
+++ b/synapse/config/redis.py
@@ -21,7 +21,7 @@ class RedisConfig(Config):
     section = "redis"
 
     def read_config(self, config, **kwargs):
-        redis_config = config.get("redis", {})
+        redis_config = config.get("redis") or {}
         self.redis_enabled = redis_config.get("enabled", False)
 
         if not self.redis_enabled:
@@ -32,3 +32,24 @@ class RedisConfig(Config):
         self.redis_host = redis_config.get("host", "localhost")
         self.redis_port = redis_config.get("port", 6379)
         self.redis_password = redis_config.get("password")
+
+    def generate_config_section(self, config_dir_path, server_name, **kwargs):
+        return """\
+        # Configuration for Redis when using workers. This *must* be enabled when
+        # using workers (unless using old style direct TCP configuration).
+        #
+        redis:
+          # Uncomment the below to enable Redis support.
+          #
+          #enabled: true
+
+          # Optional host and port to use to connect to redis. Defaults to
+          # localhost and 6379
+          #
+          #host: localhost
+          #port: 6379
+
+          # Optional password if configured on the Redis instance
+          #
+          #password: <secret_password>
+        """
diff --git a/synapse/config/workers.py b/synapse/config/workers.py
index 2574cd3aa1..c784a71508 100644
--- a/synapse/config/workers.py
+++ b/synapse/config/workers.py
@@ -15,7 +15,7 @@
 
 import attr
 
-from ._base import Config, ConfigError
+from ._base import Config, ConfigError, ShardedWorkerHandlingConfig
 from .server import ListenerConfig, parse_listener_def
 
 
@@ -85,6 +85,16 @@ class WorkerConfig(Config):
                 )
             )
 
+        # Whether to send federation traffic out in this process. This only
+        # applies to some federation traffic, and so shouldn't be used to
+        # "disable" federation
+        self.send_federation = config.get("send_federation", True)
+
+        federation_sender_instances = config.get("federation_sender_instances") or []
+        self.federation_shard_config = ShardedWorkerHandlingConfig(
+            federation_sender_instances
+        )
+
         # A map from instance name to host/port of their HTTP replication endpoint.
         instance_map = config.get("instance_map") or {}
         self.instance_map = {
@@ -105,6 +115,43 @@ class WorkerConfig(Config):
                     % (instance, stream)
                 )
 
+    def generate_config_section(self, config_dir_path, server_name, **kwargs):
+        return """\
+        ## Workers ##
+
+        # Disables sending of outbound federation transactions on the main process.
+        # Uncomment if using a federation sender worker.
+        #
+        #send_federation: false
+
+        # It is possible to run multiple federation sender workers, in which case the
+        # work is balanced across them.
+        #
+        # This configuration must be shared between all federation sender workers, and if
+        # changed all federation sender workers must be stopped at the same time and then
+        # started, to ensure that all instances are running with the same config (otherwise
+        # events may be dropped).
+        #
+        #federation_sender_instances:
+        #  - federation_sender1
+
+        # When using workers this should be a map from `worker_name` to the
+        # HTTP replication listener of the worker, if configured.
+        #
+        #instance_map:
+        #  worker1:
+        #    host: localhost
+        #    port: 8034
+
+        # Experimental: When using workers you can define which workers should
+        # handle event persistence and typing notifications. Any worker
+        # specified here must also be in the `instance_map`.
+        #
+        #stream_writers:
+        #  events: worker1
+        #  typing: worker1
+        """
+
     def read_arguments(self, args):
         # We support a bunch of command line arguments that override options in
         # the config. A lot of these options have a worker_* prefix when running
diff --git a/synapse/federation/send_queue.py b/synapse/federation/send_queue.py
index 4fc9ff92e5..2b0ab2dcbf 100644
--- a/synapse/federation/send_queue.py
+++ b/synapse/federation/send_queue.py
@@ -57,7 +57,7 @@ class FederationRemoteSendQueue(object):
 
         # We may have multiple federation sender instances, so we need to track
         # their positions separately.
-        self._sender_instances = hs.config.federation.federation_shard_config.instances
+        self._sender_instances = hs.config.worker.federation_shard_config.instances
         self._sender_positions = {}
 
         # Pending presence map user_id -> UserPresenceState
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index ba4ddd2370..6ae6522f87 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -70,7 +70,7 @@ class FederationSender(object):
         self._transaction_manager = TransactionManager(hs)
 
         self._instance_name = hs.get_instance_name()
-        self._federation_shard_config = hs.config.federation.federation_shard_config
+        self._federation_shard_config = hs.config.worker.federation_shard_config
 
         # map from destination to PerDestinationQueue
         self._per_destination_queues = {}  # type: Dict[str, PerDestinationQueue]
diff --git a/synapse/federation/sender/per_destination_queue.py b/synapse/federation/sender/per_destination_queue.py
index 3436741783..dd150f89a6 100644
--- a/synapse/federation/sender/per_destination_queue.py
+++ b/synapse/federation/sender/per_destination_queue.py
@@ -75,7 +75,7 @@ class PerDestinationQueue(object):
         self._store = hs.get_datastore()
         self._transaction_manager = transaction_manager
         self._instance_name = hs.get_instance_name()
-        self._federation_shard_config = hs.config.federation.federation_shard_config
+        self._federation_shard_config = hs.config.worker.federation_shard_config
 
         self._should_send_on_this_instance = True
         if not self._federation_shard_config.should_handle(
diff --git a/synapse/storage/data_stores/main/stream.py b/synapse/storage/data_stores/main/stream.py
index 5e32c7aa1e..10d39b3699 100644
--- a/synapse/storage/data_stores/main/stream.py
+++ b/synapse/storage/data_stores/main/stream.py
@@ -255,7 +255,7 @@ class StreamWorkerStore(EventsWorkerStore, SQLBaseStore):
 
         self._instance_name = hs.get_instance_name()
         self._send_federation = hs.should_send_federation()
-        self._federation_shard_config = hs.config.federation.federation_shard_config
+        self._federation_shard_config = hs.config.worker.federation_shard_config
 
         # If we're a process that sends federation we may need to reset the
         # `federation_stream_position` table to match the current sharding
-- 
cgit 1.5.1


From c978f6c4515a631f289aedb1844d8579b9334aaa Mon Sep 17 00:00:00 2001
From: Patrick Cloke <clokep@users.noreply.github.com>
Date: Thu, 30 Jul 2020 08:01:33 -0400
Subject: Convert federation client to async/await. (#7975)

---
 changelog.d/7975.misc                             |  1 +
 contrib/cmdclient/console.py                      | 16 ++--
 synapse/crypto/keyring.py                         | 60 +++++++-------
 synapse/federation/federation_client.py           |  8 +-
 synapse/federation/sender/__init__.py             | 19 ++---
 synapse/federation/transport/client.py            | 96 ++++++++++-------------
 synapse/handlers/groups_local.py                  | 35 ++++-----
 synapse/http/matrixfederationclient.py            | 72 ++++++++---------
 tests/crypto/test_keyring.py                      | 11 +--
 tests/federation/test_complexity.py               | 21 ++---
 tests/federation/test_federation_sender.py        | 10 +--
 tests/handlers/test_directory.py                  |  5 +-
 tests/handlers/test_profile.py                    |  3 +-
 tests/http/test_fedclient.py                      | 50 ++++++++----
 tests/replication/test_federation_sender_shard.py | 13 ++-
 tests/rest/admin/test_admin.py                    |  4 +-
 tests/rest/key/v2/test_remote_key_resource.py     |  4 +-
 tests/test_federation.py                          |  2 +-
 18 files changed, 209 insertions(+), 221 deletions(-)
 create mode 100644 changelog.d/7975.misc

(limited to 'synapse/federation')

diff --git a/changelog.d/7975.misc b/changelog.d/7975.misc
new file mode 100644
index 0000000000..dfe4c03171
--- /dev/null
+++ b/changelog.d/7975.misc
@@ -0,0 +1 @@
+Convert various parts of the codebase to async/await.
diff --git a/contrib/cmdclient/console.py b/contrib/cmdclient/console.py
index 77422f5e5d..dfc1d294dc 100755
--- a/contrib/cmdclient/console.py
+++ b/contrib/cmdclient/console.py
@@ -609,13 +609,15 @@ class SynapseCmd(cmd.Cmd):
 
     @defer.inlineCallbacks
     def _do_event_stream(self, timeout):
-        res = yield self.http_client.get_json(
-            self._url() + "/events",
-            {
-                "access_token": self._tok(),
-                "timeout": str(timeout),
-                "from": self.event_stream_token,
-            },
+        res = yield defer.ensureDeferred(
+            self.http_client.get_json(
+                self._url() + "/events",
+                {
+                    "access_token": self._tok(),
+                    "timeout": str(timeout),
+                    "from": self.event_stream_token,
+                },
+            )
         )
         print(json.dumps(res, indent=4))
 
diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index dbfc3e8972..443cde0b6d 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -632,18 +632,20 @@ class PerspectivesKeyFetcher(BaseV2KeyFetcher):
         )
 
         try:
-            query_response = yield self.client.post_json(
-                destination=perspective_name,
-                path="/_matrix/key/v2/query",
-                data={
-                    "server_keys": {
-                        server_name: {
-                            key_id: {"minimum_valid_until_ts": min_valid_ts}
-                            for key_id, min_valid_ts in server_keys.items()
+            query_response = yield defer.ensureDeferred(
+                self.client.post_json(
+                    destination=perspective_name,
+                    path="/_matrix/key/v2/query",
+                    data={
+                        "server_keys": {
+                            server_name: {
+                                key_id: {"minimum_valid_until_ts": min_valid_ts}
+                                for key_id, min_valid_ts in server_keys.items()
+                            }
+                            for server_name, server_keys in keys_to_fetch.items()
                         }
-                        for server_name, server_keys in keys_to_fetch.items()
-                    }
-                },
+                    },
+                )
             )
         except (NotRetryingDestination, RequestSendFailed) as e:
             # these both have str() representations which we can't really improve upon
@@ -792,23 +794,25 @@ class ServerKeyFetcher(BaseV2KeyFetcher):
 
             time_now_ms = self.clock.time_msec()
             try:
-                response = yield self.client.get_json(
-                    destination=server_name,
-                    path="/_matrix/key/v2/server/"
-                    + urllib.parse.quote(requested_key_id),
-                    ignore_backoff=True,
-                    # we only give the remote server 10s to respond. It should be an
-                    # easy request to handle, so if it doesn't reply within 10s, it's
-                    # probably not going to.
-                    #
-                    # Furthermore, when we are acting as a notary server, we cannot
-                    # wait all day for all of the origin servers, as the requesting
-                    # server will otherwise time out before we can respond.
-                    #
-                    # (Note that get_json may make 4 attempts, so this can still take
-                    # almost 45 seconds to fetch the headers, plus up to another 60s to
-                    # read the response).
-                    timeout=10000,
+                response = yield defer.ensureDeferred(
+                    self.client.get_json(
+                        destination=server_name,
+                        path="/_matrix/key/v2/server/"
+                        + urllib.parse.quote(requested_key_id),
+                        ignore_backoff=True,
+                        # we only give the remote server 10s to respond. It should be an
+                        # easy request to handle, so if it doesn't reply within 10s, it's
+                        # probably not going to.
+                        #
+                        # Furthermore, when we are acting as a notary server, we cannot
+                        # wait all day for all of the origin servers, as the requesting
+                        # server will otherwise time out before we can respond.
+                        #
+                        # (Note that get_json may make 4 attempts, so this can still take
+                        # almost 45 seconds to fetch the headers, plus up to another 60s to
+                        # read the response).
+                        timeout=10000,
+                    )
                 )
             except (NotRetryingDestination, RequestSendFailed) as e:
                 # these both have str() representations which we can't really improve
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 994e6c8d5a..38ac7ec699 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -135,7 +135,7 @@ class FederationClient(FederationBase):
                 and try the request anyway.
 
         Returns:
-            a Deferred which will eventually yield a JSON object from the
+            a Awaitable which will eventually yield a JSON object from the
             response
         """
         sent_queries_counter.labels(query_type).inc()
@@ -157,7 +157,7 @@ class FederationClient(FederationBase):
             content (dict): The query content.
 
         Returns:
-            a Deferred which will eventually yield a JSON object from the
+            an Awaitable which will eventually yield a JSON object from the
             response
         """
         sent_queries_counter.labels("client_device_keys").inc()
@@ -180,7 +180,7 @@ class FederationClient(FederationBase):
             content (dict): The query content.
 
         Returns:
-            a Deferred which will eventually yield a JSON object from the
+            an Awaitable which will eventually yield a JSON object from the
             response
         """
         sent_queries_counter.labels("client_one_time_keys").inc()
@@ -900,7 +900,7 @@ class FederationClient(FederationBase):
                 party instance
 
         Returns:
-            Deferred[Dict[str, Any]]: The response from the remote server, or None if
+            Awaitable[Dict[str, Any]]: The response from the remote server, or None if
             `remote_server` is the same as the local server_name
 
         Raises:
diff --git a/synapse/federation/sender/__init__.py b/synapse/federation/sender/__init__.py
index ba4ddd2370..8f549ae6ee 100644
--- a/synapse/federation/sender/__init__.py
+++ b/synapse/federation/sender/__init__.py
@@ -288,8 +288,7 @@ class FederationSender(object):
         for destination in destinations:
             self._get_per_destination_queue(destination).send_pdu(pdu, order)
 
-    @defer.inlineCallbacks
-    def send_read_receipt(self, receipt: ReadReceipt):
+    async def send_read_receipt(self, receipt: ReadReceipt) -> None:
         """Send a RR to any other servers in the room
 
         Args:
@@ -330,9 +329,7 @@ class FederationSender(object):
         room_id = receipt.room_id
 
         # Work out which remote servers should be poked and poke them.
-        domains = yield defer.ensureDeferred(
-            self.state.get_current_hosts_in_room(room_id)
-        )
+        domains = await self.state.get_current_hosts_in_room(room_id)
         domains = [
             d
             for d in domains
@@ -387,8 +384,7 @@ class FederationSender(object):
             queue.flush_read_receipts_for_room(room_id)
 
     @preserve_fn  # the caller should not yield on this
-    @defer.inlineCallbacks
-    def send_presence(self, states: List[UserPresenceState]):
+    async def send_presence(self, states: List[UserPresenceState]):
         """Send the new presence states to the appropriate destinations.
 
         This actually queues up the presence states ready for sending and
@@ -423,7 +419,7 @@ class FederationSender(object):
                 if not states_map:
                     break
 
-                yield self._process_presence_inner(list(states_map.values()))
+                await self._process_presence_inner(list(states_map.values()))
         except Exception:
             logger.exception("Error sending presence states to servers")
         finally:
@@ -450,14 +446,11 @@ class FederationSender(object):
             self._get_per_destination_queue(destination).send_presence(states)
 
     @measure_func("txnqueue._process_presence")
-    @defer.inlineCallbacks
-    def _process_presence_inner(self, states: List[UserPresenceState]):
+    async def _process_presence_inner(self, states: List[UserPresenceState]):
         """Given a list of states populate self.pending_presence_by_dest and
         poke to send a new transaction to each destination
         """
-        hosts_and_states = yield defer.ensureDeferred(
-            get_interested_remotes(self.store, states, self.state)
-        )
+        hosts_and_states = await get_interested_remotes(self.store, states, self.state)
 
         for destinations, states in hosts_and_states:
             for destination in destinations:
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index cfdf23d366..9ea821dbb2 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -18,8 +18,6 @@ import logging
 import urllib
 from typing import Any, Dict, Optional
 
-from twisted.internet import defer
-
 from synapse.api.constants import Membership
 from synapse.api.errors import Codes, HttpResponseException, SynapseError
 from synapse.api.urls import (
@@ -51,7 +49,7 @@ class TransportLayerClient(object):
             event_id (str): The event we want the context at.
 
         Returns:
-            Deferred: Results in a dict received from the remote homeserver.
+            Awaitable: Results in a dict received from the remote homeserver.
         """
         logger.debug("get_room_state_ids dest=%s, room=%s", destination, room_id)
 
@@ -75,7 +73,7 @@ class TransportLayerClient(object):
                 giving up. None indicates no timeout.
 
         Returns:
-            Deferred: Results in a dict received from the remote homeserver.
+            Awaitable: Results in a dict received from the remote homeserver.
         """
         logger.debug("get_pdu dest=%s, event_id=%s", destination, event_id)
 
@@ -96,7 +94,7 @@ class TransportLayerClient(object):
             limit (int)
 
         Returns:
-            Deferred: Results in a dict received from the remote homeserver.
+            Awaitable: Results in a dict received from the remote homeserver.
         """
         logger.debug(
             "backfill dest=%s, room_id=%s, event_tuples=%r, limit=%s",
@@ -118,16 +116,15 @@ class TransportLayerClient(object):
             destination, path=path, args=args, try_trailing_slash_on_400=True
         )
 
-    @defer.inlineCallbacks
     @log_function
-    def send_transaction(self, transaction, json_data_callback=None):
+    async def send_transaction(self, transaction, json_data_callback=None):
         """ Sends the given Transaction to its destination
 
         Args:
             transaction (Transaction)
 
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
+            Succeeds when we get a 2xx HTTP response. The result
             will be the decoded JSON body.
 
             Fails with ``HTTPRequestException`` if we get an HTTP response
@@ -154,7 +151,7 @@ class TransportLayerClient(object):
 
         path = _create_v1_path("/send/%s", transaction.transaction_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             transaction.destination,
             path=path,
             data=json_data,
@@ -166,14 +163,13 @@ class TransportLayerClient(object):
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def make_query(
+    async def make_query(
         self, destination, query_type, args, retry_on_dns_fail, ignore_backoff=False
     ):
         path = _create_v1_path("/query/%s", query_type)
 
-        content = yield self.client.get_json(
+        content = await self.client.get_json(
             destination=destination,
             path=path,
             args=args,
@@ -184,9 +180,10 @@ class TransportLayerClient(object):
 
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def make_membership_event(self, destination, room_id, user_id, membership, params):
+    async def make_membership_event(
+        self, destination, room_id, user_id, membership, params
+    ):
         """Asks a remote server to build and sign us a membership event
 
         Note that this does not append any events to any graphs.
@@ -200,7 +197,7 @@ class TransportLayerClient(object):
                 request.
 
         Returns:
-            Deferred: Succeeds when we get a 2xx HTTP response. The result
+            Succeeds when we get a 2xx HTTP response. The result
             will be the decoded JSON body (ie, the new event).
 
             Fails with ``HTTPRequestException`` if we get an HTTP response
@@ -231,7 +228,7 @@ class TransportLayerClient(object):
             ignore_backoff = True
             retry_on_dns_fail = True
 
-        content = yield self.client.get_json(
+        content = await self.client.get_json(
             destination=destination,
             path=path,
             args=params,
@@ -242,34 +239,31 @@ class TransportLayerClient(object):
 
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def send_join_v1(self, destination, room_id, event_id, content):
+    async def send_join_v1(self, destination, room_id, event_id, content):
         path = _create_v1_path("/send_join/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination, path=path, data=content
         )
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def send_join_v2(self, destination, room_id, event_id, content):
+    async def send_join_v2(self, destination, room_id, event_id, content):
         path = _create_v2_path("/send_join/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination, path=path, data=content
         )
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def send_leave_v1(self, destination, room_id, event_id, content):
+    async def send_leave_v1(self, destination, room_id, event_id, content):
         path = _create_v1_path("/send_leave/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination,
             path=path,
             data=content,
@@ -282,12 +276,11 @@ class TransportLayerClient(object):
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def send_leave_v2(self, destination, room_id, event_id, content):
+    async def send_leave_v2(self, destination, room_id, event_id, content):
         path = _create_v2_path("/send_leave/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination,
             path=path,
             data=content,
@@ -300,31 +293,28 @@ class TransportLayerClient(object):
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def send_invite_v1(self, destination, room_id, event_id, content):
+    async def send_invite_v1(self, destination, room_id, event_id, content):
         path = _create_v1_path("/invite/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination, path=path, data=content, ignore_backoff=True
         )
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def send_invite_v2(self, destination, room_id, event_id, content):
+    async def send_invite_v2(self, destination, room_id, event_id, content):
         path = _create_v2_path("/invite/%s/%s", room_id, event_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination, path=path, data=content, ignore_backoff=True
         )
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def get_public_rooms(
+    async def get_public_rooms(
         self,
         remote_server: str,
         limit: Optional[int] = None,
@@ -355,7 +345,7 @@ class TransportLayerClient(object):
             data["filter"] = search_filter
 
             try:
-                response = yield self.client.post_json(
+                response = await self.client.post_json(
                     destination=remote_server, path=path, data=data, ignore_backoff=True
                 )
             except HttpResponseException as e:
@@ -381,7 +371,7 @@ class TransportLayerClient(object):
                 args["since"] = [since_token]
 
             try:
-                response = yield self.client.get_json(
+                response = await self.client.get_json(
                     destination=remote_server, path=path, args=args, ignore_backoff=True
                 )
             except HttpResponseException as e:
@@ -396,29 +386,26 @@ class TransportLayerClient(object):
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def exchange_third_party_invite(self, destination, room_id, event_dict):
+    async def exchange_third_party_invite(self, destination, room_id, event_dict):
         path = _create_v1_path("/exchange_third_party_invite/%s", room_id)
 
-        response = yield self.client.put_json(
+        response = await self.client.put_json(
             destination=destination, path=path, data=event_dict
         )
 
         return response
 
-    @defer.inlineCallbacks
     @log_function
-    def get_event_auth(self, destination, room_id, event_id):
+    async def get_event_auth(self, destination, room_id, event_id):
         path = _create_v1_path("/event_auth/%s/%s", room_id, event_id)
 
-        content = yield self.client.get_json(destination=destination, path=path)
+        content = await self.client.get_json(destination=destination, path=path)
 
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def query_client_keys(self, destination, query_content, timeout):
+    async def query_client_keys(self, destination, query_content, timeout):
         """Query the device keys for a list of user ids hosted on a remote
         server.
 
@@ -453,14 +440,13 @@ class TransportLayerClient(object):
         """
         path = _create_v1_path("/user/keys/query")
 
-        content = yield self.client.post_json(
+        content = await self.client.post_json(
             destination=destination, path=path, data=query_content, timeout=timeout
         )
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def query_user_devices(self, destination, user_id, timeout):
+    async def query_user_devices(self, destination, user_id, timeout):
         """Query the devices for a user id hosted on a remote server.
 
         Response:
@@ -493,14 +479,13 @@ class TransportLayerClient(object):
         """
         path = _create_v1_path("/user/devices/%s", user_id)
 
-        content = yield self.client.get_json(
+        content = await self.client.get_json(
             destination=destination, path=path, timeout=timeout
         )
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def claim_client_keys(self, destination, query_content, timeout):
+    async def claim_client_keys(self, destination, query_content, timeout):
         """Claim one-time keys for a list of devices hosted on a remote server.
 
         Request:
@@ -532,14 +517,13 @@ class TransportLayerClient(object):
 
         path = _create_v1_path("/user/keys/claim")
 
-        content = yield self.client.post_json(
+        content = await self.client.post_json(
             destination=destination, path=path, data=query_content, timeout=timeout
         )
         return content
 
-    @defer.inlineCallbacks
     @log_function
-    def get_missing_events(
+    async def get_missing_events(
         self,
         destination,
         room_id,
@@ -551,7 +535,7 @@ class TransportLayerClient(object):
     ):
         path = _create_v1_path("/get_missing_events/%s", room_id)
 
-        content = yield self.client.post_json(
+        content = await self.client.post_json(
             destination=destination,
             path=path,
             data={
diff --git a/synapse/handlers/groups_local.py b/synapse/handlers/groups_local.py
index ecdb12a7bf..0e2656ccb3 100644
--- a/synapse/handlers/groups_local.py
+++ b/synapse/handlers/groups_local.py
@@ -23,39 +23,32 @@ logger = logging.getLogger(__name__)
 
 
 def _create_rerouter(func_name):
-    """Returns a function that looks at the group id and calls the function
+    """Returns an async function that looks at the group id and calls the function
     on federation or the local group server if the group is local
     """
 
-    def f(self, group_id, *args, **kwargs):
+    async def f(self, group_id, *args, **kwargs):
         if self.is_mine_id(group_id):
-            return getattr(self.groups_server_handler, func_name)(
+            return await getattr(self.groups_server_handler, func_name)(
                 group_id, *args, **kwargs
             )
         else:
             destination = get_domain_from_id(group_id)
-            d = getattr(self.transport_client, func_name)(
-                destination, group_id, *args, **kwargs
-            )
 
-            # Capture errors returned by the remote homeserver and
-            # re-throw specific errors as SynapseErrors. This is so
-            # when the remote end responds with things like 403 Not
-            # In Group, we can communicate that to the client instead
-            # of a 500.
-            def http_response_errback(failure):
-                failure.trap(HttpResponseException)
-                e = failure.value
+            try:
+                return await getattr(self.transport_client, func_name)(
+                    destination, group_id, *args, **kwargs
+                )
+            except HttpResponseException as e:
+                # Capture errors returned by the remote homeserver and
+                # re-throw specific errors as SynapseErrors. This is so
+                # when the remote end responds with things like 403 Not
+                # In Group, we can communicate that to the client instead
+                # of a 500.
                 raise e.to_synapse_error()
-
-            def request_failed_errback(failure):
-                failure.trap(RequestSendFailed)
+            except RequestSendFailed:
                 raise SynapseError(502, "Failed to contact group server")
 
-            d.addErrback(http_response_errback)
-            d.addErrback(request_failed_errback)
-            return d
-
     return f
 
 
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index ea026ed9f4..2a6373937a 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -121,8 +121,7 @@ class MatrixFederationRequest(object):
         return self.json
 
 
-@defer.inlineCallbacks
-def _handle_json_response(reactor, timeout_sec, request, response):
+async def _handle_json_response(reactor, timeout_sec, request, response):
     """
     Reads the JSON body of a response, with a timeout
 
@@ -141,7 +140,7 @@ def _handle_json_response(reactor, timeout_sec, request, response):
         d = treq.json_content(response)
         d = timeout_deferred(d, timeout=timeout_sec, reactor=reactor)
 
-        body = yield make_deferred_yieldable(d)
+        body = await make_deferred_yieldable(d)
     except TimeoutError as e:
         logger.warning(
             "{%s} [%s] Timed out reading response", request.txn_id, request.destination,
@@ -224,8 +223,7 @@ class MatrixFederationHttpClient(object):
 
         self._cooperator = Cooperator(scheduler=schedule)
 
-    @defer.inlineCallbacks
-    def _send_request_with_optional_trailing_slash(
+    async def _send_request_with_optional_trailing_slash(
         self, request, try_trailing_slash_on_400=False, **send_request_args
     ):
         """Wrapper for _send_request which can optionally retry the request
@@ -246,10 +244,10 @@ class MatrixFederationHttpClient(object):
                 (except 429).
 
         Returns:
-            Deferred[Dict]: Parsed JSON response body.
+            Dict: Parsed JSON response body.
         """
         try:
-            response = yield self._send_request(request, **send_request_args)
+            response = await self._send_request(request, **send_request_args)
         except HttpResponseException as e:
             # Received an HTTP error > 300. Check if it meets the requirements
             # to retry with a trailing slash
@@ -265,12 +263,11 @@ class MatrixFederationHttpClient(object):
             logger.info("Retrying request with trailing slash")
             request.path += "/"
 
-            response = yield self._send_request(request, **send_request_args)
+            response = await self._send_request(request, **send_request_args)
 
         return response
 
-    @defer.inlineCallbacks
-    def _send_request(
+    async def _send_request(
         self,
         request,
         retry_on_dns_fail=True,
@@ -311,7 +308,7 @@ class MatrixFederationHttpClient(object):
             backoff_on_404 (bool): Back off if we get a 404
 
         Returns:
-            Deferred[twisted.web.client.Response]: resolves with the HTTP
+            twisted.web.client.Response: resolves with the HTTP
             response object on success.
 
         Raises:
@@ -335,7 +332,7 @@ class MatrixFederationHttpClient(object):
         ):
             raise FederationDeniedError(request.destination)
 
-        limiter = yield synapse.util.retryutils.get_retry_limiter(
+        limiter = await synapse.util.retryutils.get_retry_limiter(
             request.destination,
             self.clock,
             self._store,
@@ -433,7 +430,7 @@ class MatrixFederationHttpClient(object):
                                 reactor=self.reactor,
                             )
 
-                            response = yield request_deferred
+                            response = await request_deferred
                     except TimeoutError as e:
                         raise RequestSendFailed(e, can_retry=True) from e
                     except DNSLookupError as e:
@@ -474,7 +471,7 @@ class MatrixFederationHttpClient(object):
                         )
 
                         try:
-                            body = yield make_deferred_yieldable(d)
+                            body = await make_deferred_yieldable(d)
                         except Exception as e:
                             # Eh, we're already going to raise an exception so lets
                             # ignore if this fails.
@@ -528,7 +525,7 @@ class MatrixFederationHttpClient(object):
                             delay,
                         )
 
-                        yield self.clock.sleep(delay)
+                        await self.clock.sleep(delay)
                         retries_left -= 1
                     else:
                         raise
@@ -591,8 +588,7 @@ class MatrixFederationHttpClient(object):
             )
         return auth_headers
 
-    @defer.inlineCallbacks
-    def put_json(
+    async def put_json(
         self,
         destination,
         path,
@@ -636,7 +632,7 @@ class MatrixFederationHttpClient(object):
                 enabled.
 
         Returns:
-            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            dict|list: Succeeds when we get a 2xx HTTP response. The
             result will be the decoded JSON body.
 
         Raises:
@@ -658,7 +654,7 @@ class MatrixFederationHttpClient(object):
             json=data,
         )
 
-        response = yield self._send_request_with_optional_trailing_slash(
+        response = await self._send_request_with_optional_trailing_slash(
             request,
             try_trailing_slash_on_400,
             backoff_on_404=backoff_on_404,
@@ -667,14 +663,13 @@ class MatrixFederationHttpClient(object):
             timeout=timeout,
         )
 
-        body = yield _handle_json_response(
+        body = await _handle_json_response(
             self.reactor, self.default_timeout, request, response
         )
 
         return body
 
-    @defer.inlineCallbacks
-    def post_json(
+    async def post_json(
         self,
         destination,
         path,
@@ -707,7 +702,7 @@ class MatrixFederationHttpClient(object):
 
             args (dict): query params
         Returns:
-            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            dict|list: Succeeds when we get a 2xx HTTP response. The
             result will be the decoded JSON body.
 
         Raises:
@@ -725,7 +720,7 @@ class MatrixFederationHttpClient(object):
             method="POST", destination=destination, path=path, query=args, json=data
         )
 
-        response = yield self._send_request(
+        response = await self._send_request(
             request,
             long_retries=long_retries,
             timeout=timeout,
@@ -737,13 +732,12 @@ class MatrixFederationHttpClient(object):
         else:
             _sec_timeout = self.default_timeout
 
-        body = yield _handle_json_response(
+        body = await _handle_json_response(
             self.reactor, _sec_timeout, request, response
         )
         return body
 
-    @defer.inlineCallbacks
-    def get_json(
+    async def get_json(
         self,
         destination,
         path,
@@ -775,7 +769,7 @@ class MatrixFederationHttpClient(object):
                 response we should try appending a trailing slash to the end of
                 the request. Workaround for #3622 in Synapse <= v0.99.3.
         Returns:
-            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            dict|list: Succeeds when we get a 2xx HTTP response. The
             result will be the decoded JSON body.
 
         Raises:
@@ -792,7 +786,7 @@ class MatrixFederationHttpClient(object):
             method="GET", destination=destination, path=path, query=args
         )
 
-        response = yield self._send_request_with_optional_trailing_slash(
+        response = await self._send_request_with_optional_trailing_slash(
             request,
             try_trailing_slash_on_400,
             backoff_on_404=False,
@@ -801,14 +795,13 @@ class MatrixFederationHttpClient(object):
             timeout=timeout,
         )
 
-        body = yield _handle_json_response(
+        body = await _handle_json_response(
             self.reactor, self.default_timeout, request, response
         )
 
         return body
 
-    @defer.inlineCallbacks
-    def delete_json(
+    async def delete_json(
         self,
         destination,
         path,
@@ -836,7 +829,7 @@ class MatrixFederationHttpClient(object):
 
             args (dict): query params
         Returns:
-            Deferred[dict|list]: Succeeds when we get a 2xx HTTP response. The
+            dict|list: Succeeds when we get a 2xx HTTP response. The
             result will be the decoded JSON body.
 
         Raises:
@@ -853,20 +846,19 @@ class MatrixFederationHttpClient(object):
             method="DELETE", destination=destination, path=path, query=args
         )
 
-        response = yield self._send_request(
+        response = await self._send_request(
             request,
             long_retries=long_retries,
             timeout=timeout,
             ignore_backoff=ignore_backoff,
         )
 
-        body = yield _handle_json_response(
+        body = await _handle_json_response(
             self.reactor, self.default_timeout, request, response
         )
         return body
 
-    @defer.inlineCallbacks
-    def get_file(
+    async def get_file(
         self,
         destination,
         path,
@@ -886,7 +878,7 @@ class MatrixFederationHttpClient(object):
                 and try the request anyway.
 
         Returns:
-            Deferred[tuple[int, dict]]: Resolves with an (int,dict) tuple of
+            tuple[int, dict]: Resolves with an (int,dict) tuple of
             the file length and a dict of the response headers.
 
         Raises:
@@ -903,7 +895,7 @@ class MatrixFederationHttpClient(object):
             method="GET", destination=destination, path=path, query=args
         )
 
-        response = yield self._send_request(
+        response = await self._send_request(
             request, retry_on_dns_fail=retry_on_dns_fail, ignore_backoff=ignore_backoff
         )
 
@@ -912,7 +904,7 @@ class MatrixFederationHttpClient(object):
         try:
             d = _readBodyToFile(response, output_stream, max_size)
             d.addTimeout(self.default_timeout, self.reactor)
-            length = yield make_deferred_yieldable(d)
+            length = await make_deferred_yieldable(d)
         except Exception as e:
             logger.warning(
                 "{%s} [%s] Error reading response: %s",
diff --git a/tests/crypto/test_keyring.py b/tests/crypto/test_keyring.py
index f9ce609923..e0ad8e8a77 100644
--- a/tests/crypto/test_keyring.py
+++ b/tests/crypto/test_keyring.py
@@ -102,11 +102,10 @@ class KeyringTestCase(unittest.HomeserverTestCase):
         }
         persp_deferred = defer.Deferred()
 
-        @defer.inlineCallbacks
-        def get_perspectives(**kwargs):
+        async def get_perspectives(**kwargs):
             self.assertEquals(current_context().request, "11")
             with PreserveLoggingContext():
-                yield persp_deferred
+                await persp_deferred
             return persp_resp
 
         self.http_client.post_json.side_effect = get_perspectives
@@ -355,7 +354,7 @@ class ServerKeyFetcherTestCase(unittest.HomeserverTestCase):
         }
         signedjson.sign.sign_json(response, SERVER_NAME, testkey)
 
-        def get_json(destination, path, **kwargs):
+        async def get_json(destination, path, **kwargs):
             self.assertEqual(destination, SERVER_NAME)
             self.assertEqual(path, "/_matrix/key/v2/server/key1")
             return response
@@ -444,7 +443,7 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase):
         Tell the mock http client to expect a perspectives-server key query
         """
 
-        def post_json(destination, path, data, **kwargs):
+        async def post_json(destination, path, data, **kwargs):
             self.assertEqual(destination, self.mock_perspective_server.server_name)
             self.assertEqual(path, "/_matrix/key/v2/query")
 
@@ -580,14 +579,12 @@ class PerspectivesKeyFetcherTestCase(unittest.HomeserverTestCase):
         # remove the perspectives server's signature
         response = build_response()
         del response["signatures"][self.mock_perspective_server.server_name]
-        self.http_client.post_json.return_value = {"server_keys": [response]}
         keys = get_key_from_perspectives(response)
         self.assertEqual(keys, {}, "Expected empty dict with missing persp server sig")
 
         # remove the origin server's signature
         response = build_response()
         del response["signatures"][SERVER_NAME]
-        self.http_client.post_json.return_value = {"server_keys": [response]}
         keys = get_key_from_perspectives(response)
         self.assertEqual(keys, {}, "Expected empty dict with missing origin server sig")
 
diff --git a/tests/federation/test_complexity.py b/tests/federation/test_complexity.py
index 5cd0510f0d..b8ca118716 100644
--- a/tests/federation/test_complexity.py
+++ b/tests/federation/test_complexity.py
@@ -23,6 +23,7 @@ from synapse.rest.client.v1 import login, room
 from synapse.types import UserID
 
 from tests import unittest
+from tests.test_utils import make_awaitable
 
 
 class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
@@ -78,9 +79,9 @@ class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
         fed_transport = self.hs.get_federation_transport_client()
 
         # Mock out some things, because we don't want to test the whole join
-        fed_transport.client.get_json = Mock(return_value=defer.succeed({"v1": 9999}))
+        fed_transport.client.get_json = Mock(return_value=make_awaitable({"v1": 9999}))
         handler.federation_handler.do_invite_join = Mock(
-            return_value=defer.succeed(("", 1))
+            return_value=make_awaitable(("", 1))
         )
 
         d = handler._remote_join(
@@ -109,9 +110,9 @@ class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
         fed_transport = self.hs.get_federation_transport_client()
 
         # Mock out some things, because we don't want to test the whole join
-        fed_transport.client.get_json = Mock(return_value=defer.succeed({"v1": 9999}))
+        fed_transport.client.get_json = Mock(return_value=make_awaitable({"v1": 9999}))
         handler.federation_handler.do_invite_join = Mock(
-            return_value=defer.succeed(("", 1))
+            return_value=make_awaitable(("", 1))
         )
 
         d = handler._remote_join(
@@ -147,9 +148,9 @@ class RoomComplexityTests(unittest.FederatingHomeserverTestCase):
         fed_transport = self.hs.get_federation_transport_client()
 
         # Mock out some things, because we don't want to test the whole join
-        fed_transport.client.get_json = Mock(return_value=defer.succeed(None))
+        fed_transport.client.get_json = Mock(return_value=make_awaitable(None))
         handler.federation_handler.do_invite_join = Mock(
-            return_value=defer.succeed(("", 1))
+            return_value=make_awaitable(("", 1))
         )
 
         # Artificially raise the complexity
@@ -203,9 +204,9 @@ class RoomComplexityAdminTests(unittest.FederatingHomeserverTestCase):
         fed_transport = self.hs.get_federation_transport_client()
 
         # Mock out some things, because we don't want to test the whole join
-        fed_transport.client.get_json = Mock(return_value=defer.succeed({"v1": 9999}))
+        fed_transport.client.get_json = Mock(return_value=make_awaitable({"v1": 9999}))
         handler.federation_handler.do_invite_join = Mock(
-            return_value=defer.succeed(("", 1))
+            return_value=make_awaitable(("", 1))
         )
 
         d = handler._remote_join(
@@ -233,9 +234,9 @@ class RoomComplexityAdminTests(unittest.FederatingHomeserverTestCase):
         fed_transport = self.hs.get_federation_transport_client()
 
         # Mock out some things, because we don't want to test the whole join
-        fed_transport.client.get_json = Mock(return_value=defer.succeed({"v1": 9999}))
+        fed_transport.client.get_json = Mock(return_value=make_awaitable({"v1": 9999}))
         handler.federation_handler.do_invite_join = Mock(
-            return_value=defer.succeed(("", 1))
+            return_value=make_awaitable(("", 1))
         )
 
         d = handler._remote_join(
diff --git a/tests/federation/test_federation_sender.py b/tests/federation/test_federation_sender.py
index d1bd18da39..5f512ff8bf 100644
--- a/tests/federation/test_federation_sender.py
+++ b/tests/federation/test_federation_sender.py
@@ -47,13 +47,13 @@ class FederationSenderReceiptsTestCases(HomeserverTestCase):
         mock_send_transaction = (
             self.hs.get_federation_transport_client().send_transaction
         )
-        mock_send_transaction.return_value = defer.succeed({})
+        mock_send_transaction.return_value = make_awaitable({})
 
         sender = self.hs.get_federation_sender()
         receipt = ReadReceipt(
             "room_id", "m.read", "user_id", ["event_id"], {"ts": 1234}
         )
-        self.successResultOf(sender.send_read_receipt(receipt))
+        self.successResultOf(defer.ensureDeferred(sender.send_read_receipt(receipt)))
 
         self.pump()
 
@@ -87,13 +87,13 @@ class FederationSenderReceiptsTestCases(HomeserverTestCase):
         mock_send_transaction = (
             self.hs.get_federation_transport_client().send_transaction
         )
-        mock_send_transaction.return_value = defer.succeed({})
+        mock_send_transaction.return_value = make_awaitable({})
 
         sender = self.hs.get_federation_sender()
         receipt = ReadReceipt(
             "room_id", "m.read", "user_id", ["event_id"], {"ts": 1234}
         )
-        self.successResultOf(sender.send_read_receipt(receipt))
+        self.successResultOf(defer.ensureDeferred(sender.send_read_receipt(receipt)))
 
         self.pump()
 
@@ -125,7 +125,7 @@ class FederationSenderReceiptsTestCases(HomeserverTestCase):
         receipt = ReadReceipt(
             "room_id", "m.read", "user_id", ["other_id"], {"ts": 1234}
         )
-        self.successResultOf(sender.send_read_receipt(receipt))
+        self.successResultOf(defer.ensureDeferred(sender.send_read_receipt(receipt)))
         self.pump()
         mock_send_transaction.assert_not_called()
 
diff --git a/tests/handlers/test_directory.py b/tests/handlers/test_directory.py
index 00bb776271..bc0c5aefdc 100644
--- a/tests/handlers/test_directory.py
+++ b/tests/handlers/test_directory.py
@@ -16,8 +16,6 @@
 
 from mock import Mock
 
-from twisted.internet import defer
-
 import synapse
 import synapse.api.errors
 from synapse.api.constants import EventTypes
@@ -26,6 +24,7 @@ from synapse.rest.client.v1 import directory, login, room
 from synapse.types import RoomAlias, create_requester
 
 from tests import unittest
+from tests.test_utils import make_awaitable
 
 
 class DirectoryTestCase(unittest.HomeserverTestCase):
@@ -71,7 +70,7 @@ class DirectoryTestCase(unittest.HomeserverTestCase):
         self.assertEquals({"room_id": "!8765qwer:test", "servers": ["test"]}, result)
 
     def test_get_remote_association(self):
-        self.mock_federation.make_query.return_value = defer.succeed(
+        self.mock_federation.make_query.return_value = make_awaitable(
             {"room_id": "!8765qwer:test", "servers": ["test", "remote"]}
         )
 
diff --git a/tests/handlers/test_profile.py b/tests/handlers/test_profile.py
index 4f1347cd25..d70e1fc608 100644
--- a/tests/handlers/test_profile.py
+++ b/tests/handlers/test_profile.py
@@ -24,6 +24,7 @@ from synapse.handlers.profile import MasterProfileHandler
 from synapse.types import UserID
 
 from tests import unittest
+from tests.test_utils import make_awaitable
 from tests.utils import setup_test_homeserver
 
 
@@ -138,7 +139,7 @@ class ProfileTestCase(unittest.TestCase):
 
     @defer.inlineCallbacks
     def test_get_other_name(self):
-        self.mock_federation.make_query.return_value = defer.succeed(
+        self.mock_federation.make_query.return_value = make_awaitable(
             {"displayname": "Alice"}
         )
 
diff --git a/tests/http/test_fedclient.py b/tests/http/test_fedclient.py
index fff4f0cbf4..ac598249e4 100644
--- a/tests/http/test_fedclient.py
+++ b/tests/http/test_fedclient.py
@@ -58,7 +58,9 @@ class FederationClientTests(HomeserverTestCase):
         @defer.inlineCallbacks
         def do_request():
             with LoggingContext("one") as context:
-                fetch_d = self.cl.get_json("testserv:8008", "foo/bar")
+                fetch_d = defer.ensureDeferred(
+                    self.cl.get_json("testserv:8008", "foo/bar")
+                )
 
                 # Nothing happened yet
                 self.assertNoResult(fetch_d)
@@ -120,7 +122,9 @@ class FederationClientTests(HomeserverTestCase):
         """
         If the DNS lookup returns an error, it will bubble up.
         """
-        d = self.cl.get_json("testserv2:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv2:8008", "foo/bar", timeout=10000)
+        )
         self.pump()
 
         f = self.failureResultOf(d)
@@ -128,7 +132,9 @@ class FederationClientTests(HomeserverTestCase):
         self.assertIsInstance(f.value.inner_exception, DNSLookupError)
 
     def test_client_connection_refused(self):
-        d = self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
 
         self.pump()
 
@@ -154,7 +160,9 @@ class FederationClientTests(HomeserverTestCase):
         If the HTTP request is not connected and is timed out, it'll give a
         ConnectingCancelledError or TimeoutError.
         """
-        d = self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
 
         self.pump()
 
@@ -184,7 +192,9 @@ class FederationClientTests(HomeserverTestCase):
         If the HTTP request is connected, but gets no response before being
         timed out, it'll give a ResponseNeverReceived.
         """
-        d = self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", timeout=10000)
+        )
 
         self.pump()
 
@@ -226,7 +236,7 @@ class FederationClientTests(HomeserverTestCase):
         # Try making a GET request to a blacklisted IPv4 address
         # ------------------------------------------------------
         # Make the request
-        d = cl.get_json("internal:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(cl.get_json("internal:8008", "foo/bar", timeout=10000))
 
         # Nothing happened yet
         self.assertNoResult(d)
@@ -244,7 +254,9 @@ class FederationClientTests(HomeserverTestCase):
         # Try making a POST request to a blacklisted IPv6 address
         # -------------------------------------------------------
         # Make the request
-        d = cl.post_json("internalv6:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            cl.post_json("internalv6:8008", "foo/bar", timeout=10000)
+        )
 
         # Nothing has happened yet
         self.assertNoResult(d)
@@ -263,7 +275,7 @@ class FederationClientTests(HomeserverTestCase):
         # Try making a GET request to a non-blacklisted IPv4 address
         # ----------------------------------------------------------
         # Make the request
-        d = cl.post_json("fine:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(cl.post_json("fine:8008", "foo/bar", timeout=10000))
 
         # Nothing has happened yet
         self.assertNoResult(d)
@@ -286,7 +298,7 @@ class FederationClientTests(HomeserverTestCase):
         request = MatrixFederationRequest(
             method="GET", destination="testserv:8008", path="foo/bar"
         )
-        d = self.cl._send_request(request, timeout=10000)
+        d = defer.ensureDeferred(self.cl._send_request(request, timeout=10000))
 
         self.pump()
 
@@ -310,7 +322,9 @@ class FederationClientTests(HomeserverTestCase):
         If the HTTP request is connected, but gets no response before being
         timed out, it'll give a ResponseNeverReceived.
         """
-        d = self.cl.post_json("testserv:8008", "foo/bar", timeout=10000)
+        d = defer.ensureDeferred(
+            self.cl.post_json("testserv:8008", "foo/bar", timeout=10000)
+        )
 
         self.pump()
 
@@ -342,7 +356,9 @@ class FederationClientTests(HomeserverTestCase):
         requiring a trailing slash. We need to retry the request with a
         trailing slash. Workaround for Synapse <= v0.99.3, explained in #3622.
         """
-        d = self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        )
 
         # Send the request
         self.pump()
@@ -395,7 +411,9 @@ class FederationClientTests(HomeserverTestCase):
 
         See test_client_requires_trailing_slashes() for context.
         """
-        d = self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        d = defer.ensureDeferred(
+            self.cl.get_json("testserv:8008", "foo/bar", try_trailing_slash_on_400=True)
+        )
 
         # Send the request
         self.pump()
@@ -432,7 +450,11 @@ class FederationClientTests(HomeserverTestCase):
         self.failureResultOf(d)
 
     def test_client_sends_body(self):
-        self.cl.post_json("testserv:8008", "foo/bar", timeout=10000, data={"a": "b"})
+        defer.ensureDeferred(
+            self.cl.post_json(
+                "testserv:8008", "foo/bar", timeout=10000, data={"a": "b"}
+            )
+        )
 
         self.pump()
 
@@ -453,7 +475,7 @@ class FederationClientTests(HomeserverTestCase):
 
     def test_closes_connection(self):
         """Check that the client closes unused HTTP connections"""
-        d = self.cl.get_json("testserv:8008", "foo/bar")
+        d = defer.ensureDeferred(self.cl.get_json("testserv:8008", "foo/bar"))
 
         self.pump()
 
diff --git a/tests/replication/test_federation_sender_shard.py b/tests/replication/test_federation_sender_shard.py
index 8d4dbf232e..83f9aa291c 100644
--- a/tests/replication/test_federation_sender_shard.py
+++ b/tests/replication/test_federation_sender_shard.py
@@ -16,8 +16,6 @@ import logging
 
 from mock import Mock
 
-from twisted.internet import defer
-
 from synapse.api.constants import EventTypes, Membership
 from synapse.events.builder import EventBuilderFactory
 from synapse.rest.admin import register_servlets_for_client_rest_resource
@@ -25,6 +23,7 @@ from synapse.rest.client.v1 import login, room
 from synapse.types import UserID
 
 from tests.replication._base import BaseMultiWorkerStreamTestCase
+from tests.test_utils import make_awaitable
 
 logger = logging.getLogger(__name__)
 
@@ -46,7 +45,7 @@ class FederationSenderTestCase(BaseMultiWorkerStreamTestCase):
         new event.
         """
         mock_client = Mock(spec=["put_json"])
-        mock_client.put_json.side_effect = lambda *_, **__: defer.succeed({})
+        mock_client.put_json.side_effect = lambda *_, **__: make_awaitable({})
 
         self.make_worker_hs(
             "synapse.app.federation_sender",
@@ -74,7 +73,7 @@ class FederationSenderTestCase(BaseMultiWorkerStreamTestCase):
         new events.
         """
         mock_client1 = Mock(spec=["put_json"])
-        mock_client1.put_json.side_effect = lambda *_, **__: defer.succeed({})
+        mock_client1.put_json.side_effect = lambda *_, **__: make_awaitable({})
         self.make_worker_hs(
             "synapse.app.federation_sender",
             {
@@ -86,7 +85,7 @@ class FederationSenderTestCase(BaseMultiWorkerStreamTestCase):
         )
 
         mock_client2 = Mock(spec=["put_json"])
-        mock_client2.put_json.side_effect = lambda *_, **__: defer.succeed({})
+        mock_client2.put_json.side_effect = lambda *_, **__: make_awaitable({})
         self.make_worker_hs(
             "synapse.app.federation_sender",
             {
@@ -137,7 +136,7 @@ class FederationSenderTestCase(BaseMultiWorkerStreamTestCase):
         new typing EDUs.
         """
         mock_client1 = Mock(spec=["put_json"])
-        mock_client1.put_json.side_effect = lambda *_, **__: defer.succeed({})
+        mock_client1.put_json.side_effect = lambda *_, **__: make_awaitable({})
         self.make_worker_hs(
             "synapse.app.federation_sender",
             {
@@ -149,7 +148,7 @@ class FederationSenderTestCase(BaseMultiWorkerStreamTestCase):
         )
 
         mock_client2 = Mock(spec=["put_json"])
-        mock_client2.put_json.side_effect = lambda *_, **__: defer.succeed({})
+        mock_client2.put_json.side_effect = lambda *_, **__: make_awaitable({})
         self.make_worker_hs(
             "synapse.app.federation_sender",
             {
diff --git a/tests/rest/admin/test_admin.py b/tests/rest/admin/test_admin.py
index b1a4decced..0f1144fe1e 100644
--- a/tests/rest/admin/test_admin.py
+++ b/tests/rest/admin/test_admin.py
@@ -178,7 +178,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
 
         self.fetches = []
 
-        def get_file(destination, path, output_stream, args=None, max_size=None):
+        async def get_file(destination, path, output_stream, args=None, max_size=None):
             """
             Returns tuple[int,dict,str,int] of file length, response headers,
             absolute URI, and response code.
@@ -192,7 +192,7 @@ class QuarantineMediaTestCase(unittest.HomeserverTestCase):
             d = Deferred()
             d.addCallback(write_to)
             self.fetches.append((d, destination, path, args))
-            return make_deferred_yieldable(d)
+            return await make_deferred_yieldable(d)
 
         client = Mock()
         client.get_file = get_file
diff --git a/tests/rest/key/v2/test_remote_key_resource.py b/tests/rest/key/v2/test_remote_key_resource.py
index 99eb477149..6850c666be 100644
--- a/tests/rest/key/v2/test_remote_key_resource.py
+++ b/tests/rest/key/v2/test_remote_key_resource.py
@@ -53,7 +53,7 @@ class BaseRemoteKeyResourceTestCase(unittest.HomeserverTestCase):
         Tell the mock http client to expect an outgoing GET request for the given key
         """
 
-        def get_json(destination, path, ignore_backoff=False, **kwargs):
+        async def get_json(destination, path, ignore_backoff=False, **kwargs):
             self.assertTrue(ignore_backoff)
             self.assertEqual(destination, server_name)
             key_id = "%s:%s" % (signing_key.alg, signing_key.version)
@@ -177,7 +177,7 @@ class EndToEndPerspectivesTests(BaseRemoteKeyResourceTestCase):
 
         # wire up outbound POST /key/v2/query requests from hs2 so that they
         # will be forwarded to hs1
-        def post_json(destination, path, data):
+        async def post_json(destination, path, data):
             self.assertEqual(destination, self.hs.hostname)
             self.assertEqual(
                 path, "/_matrix/key/v2/query",
diff --git a/tests/test_federation.py b/tests/test_federation.py
index 87a16d7d7a..c2f12c2741 100644
--- a/tests/test_federation.py
+++ b/tests/test_federation.py
@@ -95,7 +95,7 @@ class MessageAcceptTests(unittest.HomeserverTestCase):
         prev_events that said event references.
         """
 
-        def post_json(destination, path, data, headers=None, timeout=0):
+        async def post_json(destination, path, data, headers=None, timeout=0):
             # If it asks us for new missing events, give them NOTHING
             if path.startswith("/_matrix/federation/v1/get_missing_events/"):
                 return {"events": []}
-- 
cgit 1.5.1